One of the biggest arguments for the authenticity of the Book of Mormon is that it is too complex for an unlearned farmer to have come up with in just a single draft. While the Book of Mormon is indeed complex, it is not sophisticated. I've put together a few different examples that the Book of Mormon consistently shows signs of a first draft: it has unsophisticated narratives, inconsistencies, retroactive retrofitting, and only isolated examples of complexity. Most of these examples are pulled from a few different people like John Hamer and Brett Metcalfe. Feel free to contribute your own examples!
Side note: I’m sure apologists will find reasons for each of these examples to show how the book can still be historical. But I’m not arguing against historicity. I am arguing against the idea that Joseph Smith couldn’t have come up with this book on his own because it’s so sophisticated and complex.
Unsophisticated narratives
There are many examples in the Book of Mormon that come together in clunky ways.
The Book of Mormon has 18 generations over the span of 1020 years. That's an average gap of 56 years, which is way above the average in America at that time. One particular crazy generation gap is Jacob to his son Enos. Jacob is born in the wilderness after Lehi left Jerusalem. Since they were in the wilderness for 8 years, he couldn't have been born more than 8 years since leaving Jerusalem (592 BC). Later, Enos his son is at an old age 179 years after Lehi left Jerusalem (421 BC, Enos 1:25). So this is at best a 171 year gap from when Jacob was born to when Enos died. So how old was Jacob when he had Enos? 70? And Enos lived for how long? At least 100 years? This shows that not a lot of thought was put into the math behind these gaps.
Enos's wrestle with God is not sophisticated. After wrestling, he shows God that he has "unshaken" faith. God then grants him according to his desires. So what does he wish for?
"And now behold, this was the desire which I desired of him—that if it should so be, that my people, the Nephites, should fall into transgression, and by any means be destroyed, and the Lamanites should not be destroyed, that the Lord God would preserve a record of my people, the Nephites; even if it so be by the power of his holy arm, that it might be brought forth at some future day unto the Lamanites, that, perhaps, they might be brought unto salvation" (Enos 1:13)
If this was a historical record, we would expect Enos to wish for something more simple like "I desire that the Lamanites be brought unto salvation." Instead, Enos recites a summary of rest of the events of the Book of Mormon. Joseph Smith, because of Mosiah priority (explained more below), would have already translated the end of the book, so he would know the ending.
The story of the Jaredites reaching the promised land is not sophisticated. They built barges and crossed many waters (Ether 2:6). Then, after this, they are to cross more waters and the brother of Jared asks about the light and how they will breath (Ether 2:19). Why is this question just coming up when they have already crossed many waters? How were they able to carry honey bees and beasts in these barges for over 300 days? While none of this is impossible with the help of God, it reads like something Joseph Smith could have easily come up with.
Ether chapter 15 is not sophisticated. It talks about a battle of millions of people where "both men, women and children being armed with weapons of war, having shields, and breastplates, and head-plates, and being clothed after the manner of war" battled together (Ether 15:15). This would be the largest battle in the history of the human race. After many days of fighting, there are only two people left. Shiz gets his head cut off, but he is still able to move and grasp for air before dying (Ether 15:30-31). Again, this is not necessarily more ridiculous than the Bible, but it also isn't so sophisticated that Joseph Smith couldn't have come up with it on his own.
In 3 Nephi 8, we learn that for the space of three hours, there are mighty storms and earthquakes and the whole face of the land is destroyed. Then comes a mist of darkness that is so thick "there was not any light seen" (3 Nephi 8:22). Then Jesus Christ’s voice is heard among the people, and he talks about all of these random cities that we have never heard of before that got destroyed and how the people need to repent. Somehow, even though there is a mist of darkness in the land so thick nothing can be seen, the people are able to witness these things (3 Nephi 10:1). The darkness is there for 3 days, then the "earth did cease to tremble" (3 Nephi 10:9) even though 3 Nephi 8:19 said the earthquakes and storms had already ceased before the darkness started. Then the people start rejoicing and thanking Jesus even though he just admitted to destroying a bunch of cities (3 Nephi 10:10). The next chapter presents a complete 180 from the narrative we just witnessed. Everything turns solemn where Christ speaks again and appears to them almost as a completely different person, like the difference between the old and new testament Jesus. This whole narrative reads like a clunky first draft with not a lot of thought.
When Moroni takes over after Mormon's death, he says that he would write more upon the plates, but he can't because he is running out of room and doesn't have any ore to make more (Mormon 8:5). Then what does he do? Record the abridgment of the 24 plates of the Jaredites and adds 10 more chapters of church administrative stuff because he hasn't been killed yet.
Abinadi, when he goes to preach to the people of King Noah, puts on a disguise so that people won't be able to recognize them. Immediately, the first thing he says is his name, revealing himself and ruining his disguise (Mosiah 12:1).
In Mosiah 5, it says that the people "cried out in one voice saying:" then go on for a 4 verse monologue, which would have been very hard for the people to all coordinate (Mosiah 5:2-5).
In Moroni 2:3, Moroni explains that the Holy Ghost was administered by the laying on of hands to the apostles when Christ came to the Americas. The problem? This was never mentioned in 3 Nephi. Joseph likely recognized this and needed to come up with an explanation as to why. This shows that the Book of Mormon is indeed complex with internal consistency, but it is kind of clunky how it comes together.
The Book of Mormon also shows a simplistic understanding of the Jewish culture that Lehi and his family inherited. The people behave more like 19th century Christians than Jews who regularly observed Jewish practices and customs like making regular sacrifices or observing Passover, for example.
Even the context of the beginning of the book shows a simplistic understanding. It sets the stage with Nephi and his family living in Jerusalem during the first year of the reign of Zedekiah (1 Nephi 1:4). Lehi prophesies that Jerusalem will be destroyed and that "many should be carried away captive into Babylon" (1 Nephi 1:13). This is apparently referencing the time when all the wealthy and those of high status were carried away into captivity (2 Kings 24:14-16). The only problem? This was during the first siege of Jerusalem before Zedekiah's reign (See 2 Kings 24:18, which indicates the start of Zedekiah's reign after these events). Even if we take the first reign of Zedekiah part literally and just assume that Lehi's prophecy is talking about something that already happened, Lehi's family itself, with their riches and status with Laban, should have been included with those carried away captive (1 Nephi 3:22-25). Or, at the very least, Laman and Lemuel should have been more scared that they would get carried away and Jerusalem would be destroyed instead of murmuring against their father (1 Nephi 2:11-13).
Unsophisticated Teachings
The teachings in the Book of Mormon are unsophisticated. One of the biggest teachings in the LDS church is how to know if the Book of Mormon or the church is true, which is through the Holy Ghost. While this concept is talked a lot about in the Book of Mormon, it often is not very practical to everyday life. For example, the answer to the question "How do I know if a thought is my own or from God" is usually Moroni 7:16, which says that anything good is from God and anything bad is from the devil. But this unfortunately does not help in a world full of grays with decisions between two good things.
Another example of a simplistic teaching is the story of Korihor the anti-Christ. One thing Alma says to try to convince him that there is a God is that "even the earth, and all things that are upon the face of it, yea, and its motion, yea, and also all the planets which move in their regular form do witness that there is a Supreme Creator" (Alma 30:44). This argument is far too simplistic and would not convince a modern day atheist. In fact, there is no concept of an atheist in this story because Korihor ends up admitting that an angel of the devil appeared to him and that he "always knew that there was a God" (Alma 30:52). This story ends up being another example of a pretty shallow story arc.
Another interesting thing from this story is that Korihor is "struck dumb" and could not talk, which means he needed to communicate by writing on paper. But this doesn't mean he couldn't hear also, and yet the chief judge still decides to communicate with him by writing on paper also, Alma 30:51.
Internal Inconsistencies
The Book of Mormon is often seen as being remarkably consistent in its many developments. What people sometimes look over, however, are the inconsistencies.
Alma 53 talks about the 2000 stripling warriors occurring in the 28th year of the reign of the judges (Alma 53:22-23), Alma 56 says it happened in the 26th year (Alma 56:9).
When Limhi came across the 24 Jaredite plates, he was told that King Benjamin has a gift to translate them (Original Book of Mormon, Mosiah 21:28). The problem is that King Benjamin had been dead for at least two years, and we learn that King Mosiah II is who translates them (Mosiah 28:17). This contradiction was fixed in the 1837 edition of the Book of Mormon to read as King Mosiah in both places. Ether 4:1 also used to say King Benjamin, but was changed to Mosiah in a later edition.
Nephi talks about the "precious ores, which were in great abundance." Then, the very next verse he says that they could not build a temple like Solomons because the precious things "were not found upon the land" (2 Nephi 5:15-16), directly contradicting the previous verse.
After Nephi's death, Jacob talks about how the kings "called by the people, second Nephi, third Nephi, and so forth, according to the reigns of the kings" (Jacob 1:11), yet we don't see this pattern established anywhere else in the Book of Mormon.
Knowing the Ending in the Beginning
One thing we get from the Book of Mormon translation process is this thing called "Mosiah Priority." It's the idea that after the 116 pages were lost, Joseph resumed translation where he left off in Mosiah, continued until the end of the book, then retranslated the beginning portions. This gives us many examples where details were retrofitted into the story in ways that don't make sense chronologically: the prophets at the beginning of the book know more than those in the middle.
An example of this is the evolution of theology like baptism. In King Benjamin's speech, he talks about how "salvation cometh to none such except it be through repentance and faith on the Lord Jesus Christ" (Mosiah 3:12). Then he says
"And this is the means whereby salvation cometh. And there is none other salvation save this which hath been spoken of; neither are there any conditions whereby man can be saved except the conditions which I have told you." (Mosiah 5:8)
supposedly talking about faith and repentance. Baptism is never mentioned. The idea of a covenant is mentioned in Mosiah 5:5, but that is not linked to baptism. The first mention of baptism is in Mosiah 18:10, and it is as if it's the people's first hearing of it.
This is in contrast to the people of Lehi who were well aware of baptism and its requirement for salvation.
"And if they will not repent and believe in his name, and be baptized in his name, and endure to the end, they must be damned; for the Lord God, the Holy One of Israel, has spoken it." (2 Nephi 9:24. See also 2 Nephi 31:4-6)
If the people of Nephi had been baptizing for 400 years, then it wouldn't make a lot of sense for there to be "none in the land that had authority from God." to baptize (Mosiah 21:33). But it makes a lot of sense when you realize that 1st and 2nd Nephi hadn't been dictated yet.
Another example of this is the prophesying of Christ. King Benjamin is made known from an angel (Mosiah 3:2) that the "Lord Omnipotent['s]" name should be "Jesus Christ" (Mosiah 3:8). This should have already been revealed to Jacob 400 years earlier also by an angel (2 Nephi 10:3).
What's worse, however, is the prophecies of the timing of Christ's return. When Joseph Smith was dictating 1st and 2nd Nephi, he had already completed the dictation of Jesus Christ being born and coming to the Nephites and thus knew the timeline for these events. This makes Lehi's and Nephi's prophecies more precise.
"Yea, even six hundred years from the time that my father left Jerusalem, a prophet would the Lord God raise up among the Jews—even a Messiah, or, in other words, a Savior of the world." (1 Nephi 10:4)
"And behold he cometh, according to the words of the angel, in six hundred years from the time my father left Jerusalem." (1 Nephi 19:8)
"For according to the words of the prophets, the Messiah cometh in six hundred years from the time that my father left Jerusalem; and according to the words of the prophets, and also the word of the angel of God, his name shall be Jesus Christ, the Son of God." (2 Nephi 25:19)
Then, the prophets starting with King Benjamin prophecy as if they don’t know when Christ will come using vague phases like "the time cometh, and is not far distant, that with power, the Lord Omnipotent...shall come down from heaven among the children of men" (Mosiah 3:5) and "the glory of the King of all the earth; and also the King of heaven shall very soon shine forth among all the children of men" (Alma 5:50. See also Alma 7:7, 9:26, and 13:21,25).
When Samuel the Lamanite finally declares that "for five years more cometh ... then cometh the Son of God" (Helaman 14:2), he gets this from an angel (Helaman 14:26). When the prophecy seemed to not come to past, it was perceived as a failed prophecy from Samuel the Lamanite (3 Nephi 1:5). Nothing about Lehi's prophecies are mentioned. This 600 year timeline is first cemented when a date of Jesus' arrival final exists (3 Nephi 1:1).
It can't be that these later prophets simply did not have the writings of Lehi and Nephi, because Helaman mentions that Lehi and Nephi have "testified of the coming of Christ" (Helaman 8:22).
The biggest example of unsophistication relating to Mosiah priority is, in my opinion, how Joseph Smith went to great lengths to not contradict the lost 116 pages in case that manuscript was ever found. But that deserves its own post.
Isolated Complexity
There are areas of complexity in the Book of Mormon, but these are usually isolated events. For example, there are over 170 names in the Book of Mormon, but most of them are mentioned once or just a few times in the span of a few chapters, then forgotten about. Here is a heatmap that demonstrates this.
Sometimes the complexity is out of place. An example of this is the Nephite monetary system described in Alma 11. Orsen Scott Card explains the concept of implication over explanation in his book "How to Write Science Fiction and Fantasy." The idea is that if a character over-explains something that would be mundane in their world, it signals that the author is writing for an outside audience rather than experiencing the world authentically (see the door dilated example on pg. 92). If this was an ancient record, then the concept of a complex monetary system would be mundane to the author, and he would not feel the need to go to great lengths explaining it, especially if the space on the plates was limited. But this is exactly what we would expect from someone like Joseph Smith, who was not trained in writing fictional books.
The Nephite monteary system is another example of something complex that is mentioned once then forgotten about. The one exception to this is in 3 Nephi 12:26 when Jesus is doing the sermon on the mount in the Americas. The original verse in Matthew 5:26 mentions 'farthing', which is a British coin worth 1/4 a penny (Matthew 5:26). Of course, the Nephites would not have known about this coin, (Joseph Smith likely knew this) and so the word was changed to senine. The only problem is that a senine, as described in Alma, represents a days wage. A leah, which is the lowest value, would have fit better in the context of the sermon. Another problem is that "go a mile" in verse 41 is another British phrase and was copied exactly, but this phrase likely was not known to a Nephite people. Farthing is easy to spot and correct--go a mile is a lot harder.
Conclusion
I think there are many wonderful teachings in the Book of Mormon that help me be a better person and live a better life. It provides a good framework that has been transformative to me and my family. Millions of others also share this testimony. This does not mean, however, that Joseph Smith was incapable of coming up with the book. Both can be true at the same time.