I’m familiar with the original series; were there any differences in characterization or plot that you thought were improvements to the series, or anything you didn’t care for in that regard?
I particularly liked how Aang was portrayed. The weight of the world showed in his emotions, especially the very last scene of the movie, when the Water Nation bowed to him - the look on his face said it all. And the scene earlier when he returned to the monk's temple and saw the devastation; "I was just here yesterday!"
I do hope the producers let Shaymalan make the remainder of the 3-part series. I think the final battle with the Phoenix King in live action/CGI would be awesome.