1. Totally should've gotten a sequel
Nimona by Noelle Stevenson
Harry Potter. I would love a Marauders spin off series more than anything.
Jandy Nelson. I really enjoyed both her novels - The Sky is Everywhere and I'll Give You the Sun. I love her writing style and the characters and settings. I would love to read something new written by her.
4. A character who totally should've ended up with someone else
In the Cormoran Strike series by Robert Galbraith (aka J.K. Rowling) in the most recent book, Career of Evil, it seemed like two characters were going to get together at the end. I'm definitely not a fan of that. I don't particularly like either of the characters with the people they are with, either, but I also don't like them together. So I hope that's not the direction the series is heading.
5. Totally should've ended differently
Allegiant by Veronica Roth. Not because of a specific plot event that is a huge spoiler, but because of the entire explanation for what divergence is. I thought this book was poorly written, and I just generally didn't like the direction this series took.
6. Totally should've had a movie franchise
I don't know about franchise but I would like to see a movie adaptation of Looking for Alaska by John Green. He is a super popular author now and two of his other books have been made into movies. I'd like to see this one on the big screen.
7. Totally should've had a TV show
The graphic novel series Fables. The show Once Upon A Time is similar in premise, but the characters and plot are totally different, and while I did actually like the first one or two seasons of Once Upon A Time, I would love to see a Game of Thrones-style mini-series adaptation of Fables, on HBO or Showtime, with all the sex and violence left in.
8. Totally should've had only one point of view
The only one I can think of is Allegiant again. The voices weren't different enough and it was strange to add a dual narrator for only the last book in the series. I get why Roth did it, but it made that certain plot point more predictable and I don't think it added anything to the story because the characters were in the same place for most of the events of the book so the second perspective didn't contribute anything to the narration.
9. Totally should have a cover change
Colorless Tsukuru Tazaki and His Years of Pilgrimage by Haruki Murakami.
I really disliked the cover of this when it was released in North America. I waited and bought the paperback edition because I thought it was better, but it still doesn't match any of my other Murakami books, which kind of bugs me.
10. Totally should've kept the original covers
Anna and the French Kiss by Stephanie Perkins. I bought this book before it was a sort-of "series" and I actually like the sunset covers way better than this ugly hardcover one, so I guess I actually think that those should have been the original covers and then they shouldn't have changed. I kind of cheated this question because I like the changed cover better than the original, I just wish I had it instead.
11. Totally should've stopped at book one
Wicked by Gregory Maguire.