Aang is such a delight! I adore seeing him around Kiseki, interacting with everyone, and his intro and re-intro remain some of my favorites ever just because they were so cute. Aang is such a joy, and I especially love seeing him interact with everyone with his optimism and viewpoints in life, and wow way to break my heart with his threads with Kya and Korra in terms of the future of the air nation.
Just in general, you handle him so perfectly. He never comes across as flat or impersonal, never seems OVERLY cheerful or falsely so. He always presents perfectly genuine and kind. I love his particular brand of teasing (a necessary thing when it's a you character, of course) and his threads with Appa were so cute and fun!
And while he's such a fun and silly character, you handle his more serious Avatar-side so well! A lot of his issues have been resolved due to his canonpoint, but those never seem ignored or tossed aside. They're always present without overcoming his character, and it's clear to see his growth and life experience without overshadowing his fun personality. You handle all sides well and I love seeing his goofiness as well as his spirituality.