I watched it much later than t came out as I was at the age when it did I thought it seemed lame.
In essence, it is perfectly fine with a couple of sprinkles of stand out elements. Zuko's character arc is really good and the best in the show, imo. Zuko ended up getting sidelined in a stupid end decision though... towards the end you could see them slowly descending into the mindset that brought us fucking Korra.
As the series neared it's end they lost sight of why people liked the characters, specifically Katara. Katara was a human character with strengths and flaws... one of which was not being super talented at bending. This was shown well with her frustration with Aang outpacing her even in waterbending. However, she couldn't remain that way when there is sexism to bring up, oh boy! The culture where woman were expected to just use it for healing and her fighting against that was fine at the time (I can only imagine how terrible it would be written in current year...) but the fact she ended up to be the one to fight and beat fucking Azula was stupid as hell. That should have been Zuko's fight both from a prowess and character standpoint. It also just tossed off Katara's flaw and had her beat a fucking natural prodigy, so guess she's perfect now... girl power! This famously gets hilariously and exponentially surpassed in The Legend of Korra... at least it resulted E;R's videos.
