Hello everyone, this is my first post here. With the resurgence of the fandom thanks to the movie, there have been many discussions about how poorly Katara's character was treated post-canon (at least on Twitter). But I think this problem exists in the original series, and (at least I haven't seen) it discussed. I'm referring to the theme of "destiny."
Both Zuko and Aang are told, in a way, that their destinies are written (Zuko's being to capture the Avatar to reclaim his place on the throne, and Aang's being to kill the Fire Lord to bring peace to the world), yet both managed to change their destinies.
Even the entire episode about Aunt Wu hints that destiny isn't always what it seems; even Aang, whose future didn't include a girl, ended up with Katara. Meanwhile, Katara's destiny didn't seem important enough to be changed; it's as if the character resigned herself to simply accepting what she was told.
I always considered that unfair, since it's understood that only the strongest (Aang, Zuko) can change their destinies/futures, and Katara ending up with Aang just because he's "the strongest" defeats the purpose of Aunt Wu's message.
I apologize if anything is misspelled; I used a translator for this.