Next ultimate skin concept/prediction (maybe?)

So now we have Pulsefire Ezreal as a marksman, Spirit Guard Udyr as a jungler, DJ Sona as a support and Elementalist Lux as a midlaner, which means the next ultimate skin will be for a toplaner.

Before wondering which champion would have it, I started to wonder in which way it could have an evolutive model. I immediately tought of a model swapping based on which character you're playing with, according to its lore, for example, if I play with a Demacian, the model can change to accord to the demacian style or if I play against a Demacian, the model can change for a noxian style. That way we'll have:

Demacian Style: Light gold, blue and clear colors with light effects, similar to Garen's or Xin Zhao's outfit.

Noxan Style: Black, red and dark colors with dark efffects, similar to Darius's or Katarina's outfit.

Freljordan Style: Dark grey, white and cold colors with icy effect, similar to Sejuani's and Braum's outfit.

Shuriman Style: Gold, red and desert-like colors with sand/rock effect, similar to Azir's or Sivir's outfit.

Piltover Style: Hextech/steampunk style with hextech effects, similar to Caitlin's and Jayce's outfit.

Zaun Style: Punk style mixed with techmaturgy, similar to Ekko' and Viktor's outfit.

Bilgewater Style: pirate/sea-related style, with gunpowder effects,similar to Gangplank's and Illaoi's outfit.

Shadow Isles Style: Dark blue black and turquoise with a lot of floating rags with black mist effects, similar to Karthus's and Kalista's outfit.

Void Style: Purple with bolts and void-like stuff with void effect, similar to Malzahard's and Kassadin's outfit.

Yordle Style: Transforms into a yordle. (Yeah I don't have too much idea)

Targonian Style, Ionian Style: I don't really have any idea for these :/

Kumungu Style (?): Since rengar, Zyra, Nidalee (and probably Gnar) lives there, why not some sort of hunting/tribal/prehistorical outfit?

That way, we have 12 different forms that can each have a different effect.

Now the question is on which champ could these forms occur. My first choice goes to Riven, accorsing to its lore she is independent, she could be some sort of mercenary that could help people to forgive what she had done. Also the effects I listed might look good on her. My second choice is Jax, kind of for the same reasons but also because beside him and Riven I see nobody that could fit the role and the model changing concept.

What do you think about it?

Sorry for the boringness of this text, I did it on phone and consequently don't really have the right tools to make a proper discussion. ^_^'

Feel free to comment, give your advice, I would like as much feedback as possible.

See you on the rift!