I've only seen the film once and will need more viewings to get more in-depth thoughts on it, but I thought it was great! The Hunger Games adaptations are fantastic imo, so I was really pleased that this one kept up the same level of quality both as a film and as an adaptation
I was really impressed with how they incorporated the amount of songs they did from the book. I wasn't sure how many, if any, of them were going to be included considering how many of them there are, and while they work in a book, it could really mess up the flow in a non-musical film to just watch a character sing. But they used them so well!
And right now, I can't think of anything I wish they had done differently. I'm sure there's something, and with repeat viewings I could probably nitpick a bunch of things, but I don't think nitpicking minor details is very helpful. The changes they made, that I can remember, I thought made sense. They streamlined some events that took longer in the book, but I think that worked for the pacing of the movie. It's already two and a half hours after all!