Speaking with Michaela Jill Murphy, the original voice of Toph Beifong from the 2005 TV show, Avatar: The Last Airbender, Cameron was asked which Avatar was the best. To which the director admitted that since his children are bigger fans of the beloved animated series, he believes that The Last Airbender is better.
https://fandomwire.com/james-cameron-reveals-his-kids-prefer-avatar-the-last-airbender-to-avatar/
Korra was a better avatar. I got tired of Aang being a whiny, insecure child. Both series are very good, though.