I love ATLA. It was my favourite show as a kid. As an adult, I still think it's great. What sticks me out to me now is how much of a "kid's show" it is. There is no subtlety or ambiguity in what the characters are thinking/feeling or in the narrative themes. Hearing them talk about destiny and honour comes off heavy-handed now. Anime is super guilty of this too. Book 3 dropped the ball a bit, but I knew that as a kid. Still great. Siege of the North is kino.