Back in Warhammer Fantasy, I always wanted to see an eastern/samurai type army.
Now that we are into AoS, they would maybe be from Ghyr? They harness the elements, so their playstyle could be really depend / be buffed by their environments aka what realm they are in. ( not just magic ) fight alongside crazy beasts and Oni-like creatures and although not super strong themselves, they are discipled with martial prowess. They are part of different clans that signify different principles ( with designated colours and symbol ) but work harmoniously to acheive goals. Not sure what to call them yet but here are some thoughts...
Heros:
Jade Priestess standing a top a Jade Dragon ( think like cloud serpent )
Master Elementalist atop a Beast of Ago ( 47 Ronin reference ) give some antlers or something crazy
Simple Elementalist
Monk type heros (glass cannons essentially)
Elites:
Oni type beasts - bit bigger than an ogor, 3 to a unit. Heavy hitters
Samurai Cavalry - riding tigers...? Two headed tigers...( land of lore 3 reference ) or Battlecats...
Heavy armored samurai - think of the movie suckerpunch
Battleline:
Longbowman
Female warriors - kinda what they have just done with the cypher lords... Just but look more like nobushi from For Honor game
Monks
Ninjas... Obviously. Cool to set them up in Ambush or like wise rules
That's what I have so far. Maybe a bit stereotypical in some areas but I haven't thought about this in a while and ideas are flooding back to me. Some things I have not explained in as grandeur detail as I feel I should but I always thought this has been an area unexplored by GW and would love to see their take on it.
Cheers!