This not counting the finale, however. Amon was a pretty well developed and interesting villain that kept people guessing, had an agenda, and put it into action rather well. He was mysteriously ten steps ahead of everyone, and yet his being this planned was completely believable - not something easy to do with a villain. However, I do agree, the ending did fuck everything up with his character. And the fact they murdered his character on both a literal and metaphorical level in the finale was pretty lame.
Along with that, you're missing a whole lot of inconsistencies with the plot, TBH. They did only think they had one season to write a story for at the start, so it kind of makes sense that it moves at a fast as fuck pace. However, they didn't explain how Amon/Noatak and Tarlok ended up on their father's revenge vendetta after pretty much deciding they hated him. They didn't resolve a the two love triangles that they were pretty much pushing through the entire series. They didn't explain how Tenzin and Co. ended up captured, etc.
However, was I the only one EXPECTING Aang to pull the stupid bullshit save? I mean, energy bending was created as a cop out in the first season when they didn't know how to deal with the whole morality of having to kill the fire lord in a kids show... So let's create a new type of bending that totally just gets rid of the moral choice and leaves everyone happy! Wasn't surprised they did it again for this season.
