Honestly Sokka's character arc is one of my favorites. Really illustrates that he wants to do right by his community but just... doesn't have the maturity or skills to act on it, but once he's out of his comfort zone he really comes into his own
I really don't like how they handled Kataang, the resolution just felt...forced and shoehorned, after Katara spent the entire series treating Aang more like a little brother than a love interest.
(If they were going to make it canon, it would've benefited from not happening until after a time skip to when Aang wasn't, y'know. Barely into puberty?)
'Yep, this shoehorned romance between a kid who fell in puppy love at first sight and his mom friend who treated him more like a little brother right up until it was time to canonize the romances sure did last their whole lives.'
Azula would not have waited another sixty years for supreme rulership and she's been given a reeeeeeal unhealthy model to follow on "dealing with family members who are in your way"
Aang: "No it isn't!"
Iroh: "Actually it kind of is"
"Yes, princess."