Can I just say
he took lightning
To the HEART
Zuko’s entire redemption arc was leading up to his relationship with katara, the episode where they track down her mother’s killer was the climax of zuko’s personality curve, that episode SHOULD have ended with them becoming romantically involved, or at least introduced it as a possibility with it becoming a reality after his Agni-Kai with azula. Aang was the perfect “not every hero gets the girl” character from the very beginning, if he did end up married with kids it should’ve been a later development with someone else.
and katara’s entire romantic story makes SO. MUCH. MORE. SENSE. with her and zuko being in love. Her “forgiveness and healing through accepting the past and embracing the future” story complements his “trying to be good but finding it really difficult” story so beautifully. He was never her abuser, he never actually even hurt her, they were on opposite sides of a war and then they became friends. They should’ve been more.
And mai should’ve ended up with ty lee. Obviously.