thinking abt a mdzs atla au... but ive only rly got the liek. bending down for the characters ..
yunmeng is full of mostly waterbenders, but jiang cheng and madam yu are firebenders (because. zidian. lightning)
jiang yanli is more focused on healing, wwx is also a waterbender (maybe the avatar idk yet. mmmmaybe.) but hes more on the combat side of it. yllz uses bloodbending without needing a full moon
qinghe is full of earthbenders, but i think nhs would be an airbender
lanling is have the highest amount of non-benders. i think jzx is a non-bender tbh though (when he's born) jin ling is a waterbender like his mama
gusu is full of airbenders. they literally live amongst the clouds...
qishan was majority firebenders but any wens who didnt want to deal with wrh got absorbed by the other great sects. wen qing was an excellent healer despite healing usually being seen as a waterbender thing and wen ning was a non-bender but knew how to chi-block (like ty lee) i think a-yuan would also be a non-bender... perhamps.
i think i might make wwx the avatar but when he falls into the burial mounds hes severed from his past lives and kind of just. assumes that the role of avatar dies with him. except his spirit lingers for ~13ish years and so when mo xuanyu (a non-bender) sacrifices his soul to bring wwx back, the avatar state is restored (though wwx is still technically the first avatar again)
(also wen ning is Mostly Alive due to a mix of spirit water healing and medical bloodbending)