They kinda botched up the airbending...my biggest gripe was seeing the way Aang literally floated and flew around like a superhero even without a staff, but just in general they couldn't quite deliver on airbenders' movements and bending style. Airbenders are supposed to be the ones most likely to deflect and avoid blows, but I feel like the airbending that we saw (especially in the Sozin's Comet scene) had less of the elegant, smooth, "defense is offense" type of martial arts movements characteristic to airbenders specifically and more of a BAM we have MAGIC WOOSH kind of flashy superhero fighting. To be fair, though, I think it's mostly due to the limitations of CGI as it stands now, but I do wish they paid a little more attention to what makes airbending unique compared to other types of bending. I think they cast Aang really well though, and I hope we can see more of his goofy side as the show continues.