To explain my book list…adding Mark Twain. One, he a Classic Literary Author, and I think for a well-rounded reader, they will read the classics, whether they like them or not. Yes, he can be hard to read at times, but he is a great author when it comes to learning how to analyze books.
He is hard to read because of his colloquial style of writing. You almost have to read his books out loud in order to get it. He is also a satirical writer, so you have to understand the time period setting of the book to “get it”
I am not a big fan of Tom Sawyer and Huckleberry Finn, but I did like A Yankee in King Arthur’s Court. I have not read his Joan of Arc, but have read some mixed reviews on that one.