I feel that the book is a victim of the series' earlier success in many regards. But my first complaint is not pertaining to that. The first complaint is NAMES. This book has AT LEAST 70 names and it is unbelievably difficult to keep track of all of them. The first book is cleverly set up where it establishes the districts each have a different industry and that a class system is present among the 12 districts. Therefore, when you read "the boy from District 1," you can infer a lot more about the character (such as the fact he likelier stronger, better fed and wealthier) than if they said his name Marvel. This book is kind enough to give you the names of ALL 24 tributes. So when you read the scenes involving the games, you're constantly flipping back to where they mentioned which district they're from. And on top of that, they give you the names of all 24 mentors despite the fact they disappear from the book for the last third and didn't even do anything worthy of mentioning their names in the first two thirds. Perhaps 7 of the mentors deserved to be addressed by name. Right there you have 48 names. But it obviously doesn't stop there. I say "at least 70" but it would not surprise me if there's over 100 names in total. And yes, 100 names of characters that show up in at least more than one scene.
With regard to my previous comment on the book being a victim of the series' earlier success, I can easily tell that the original trilogy was written (or largely outlined) prior to the publication of the first novel. This prequel is so obviously an afterthought, it is sometimes painful. The biggest complaint i have is that the book so desperately wants to tie into and reference the trilogy (greatest example being "LOOOK. A girl from District 12!!! LIKE KAAAATNNIISSSS! GET IT?!") that it often outlines events so extraordinary that it's baffling how none of it comes up in the original trilogy. I don't think I'm spoiling anything when I say the biggest question you'll have on your mind in the end will be "Why didn't Katniss ever think of this Lucy Gray girl in the original trilogy?" On the second to last page (not even kidding) they try to give some last ditch explanation that some readers may buy but I can't. This book feels like an above average fan fiction and invested all of its time investigating a mostly uninteresting series of events rather than questions that interested the audience of the originals.