Have at it!
I was infuriated that nobody came to Katniss with an explanation about what was happening when she was in the holding cell after killing Coin. It was bothered me that justice was being done in secret (or away from the accused, at least), which made it feel like society wasn't changing all that much after all. I guess you can't expect huge shifts immediately, but more transparency would seem to be the first thing in a more open regime.
Also, did anyone ever get confirmation of who ordered the bombs dropped on the children? I think Coin and the rebels is a pretty safe assumption, but did anyone ever say for sure?