Wow. What a crappy last book. Let me count the ways... 
 (view spoiler)[ 
 Katniss basically spends most of the book in the exact same state she hated her mother for when her father died. 
 She spends the whole book not doing things. 
 The "love triangle" just dies. She doesn't end up choosing. I don't think she loved either, from the way she kept on going back and forth between the two. 
 The way she voted in the election was totally out of character - or if this is who she had become, I no longer like her. 
 Overall, this would perhaps have been more successful if she had become someone we knew that we were supposed to loath, because the experience has changed her for the worse. Or, she should have risen above it all to be the hero we wanted her to be. She doesn't live up to either. What a dissapointment. I can't help but think, hope, that they will give her more agency in the movie version. Fingers crossed. (hide spoiler)]