Honestly I thought the Legend of Korra season finale was meh. [spoilers] The whole Korra/mako thing is generic and lots of things were rushed, especially the conflict between Asami and her father and the ending. But there were lots of action plane scenes, that was cool. Overall I was not satisfied though. It's a great show as a whole of course, I mean they only were allowed a 12 episode mini series at first and this is what it was supposed to be, but Nickelodeon ordered another season. Hopefully they can spread it out and make it longer, and maybe there can be some more Amon backstory in there, because hes a great character.
The more i think about it though the more it seems the events of the last two episodes of the legend of korra could have been extended to make the season into 20 episodes, like the original series. There's so much that was rushed and left out at the wrong times, it would have been amazing to have something like a 3 episode flashback fully explaining Amons story and not leaving out any details. Oh well. What's done is done...