When you take a beloved book and turn it into a movie there are always going to be people who are saying "it would have been better if..." But, the reality is there is only so much you can do with a movie while staying true to the book. Gary Ross really captured that. They were able to move away from Katniss' narration in the book and show what was going on outside of the arena. For a 2 hr 22 min movie it flew by. The acting was great and everyone on the movie did a fantastic job.
I think it was a great movie for a book adapation. However, I don't think it would do so well if it was just a free standing movie/series. Those who have read the books go in with different expectations than those who haven't read them. I've heard a lot of "it really lagged in the middle", well for those who have read it they know that is what happens in the book as well. It's all about Bella being in depression and trying to build a friendship with Jacob. Overall, I think it really lived up!