I really haven't had time to play many games in the past week, but I have watched a metric ton of Avatar. Not the movie, about which I have heard absolutely nothing good, but most of the animated series that exists. I can say concretely that I really, really enjoy watching both series, but I currently prefer The Last Airbender to Legend of Korra.
Allison and Nicholle have seen the same amount I have, and Allison raised an interesting point: the protagonist of The Last Airbender was pretty OP much of the time, and Korra had to deal with real consequences of her actions. That is a valuable point, and one of the things that makes Korra really watchable. But I think that The Last Airbender possesses a subtlety that drives its message home more, for me at least. IT could be that they had a longer time to tell the first story. I know anecdotally how incredibly difficult it is to get a television made and kept on the air for any length of time, so the fact that The Last Airbender got the time to tell its story, and tell it well, is amazing. The creators of Korra had only a single season to work with, and I think that worked against them.
A story being not having enough time to be told is a tragedy. My hope is that we will have the time to spin all the story we want with Captain Quail and the crew of the Egg Surprise, but time will tell.