Hm. It seems I lost another post. Any way, I have graphics for fur-clad Archers, can do graphics for Fox Warriors clad in white fur, some kind of shaman should be doable (I already did something for Oglala mod, that just needs a bit more clothes), Horse Brothers are fur-clad horsemen...
We can't add a theme, but we can add a nation. Of course, this calls for a special scenario in a new map (Scandinavia), with Nerfix's nation in the middle, Vanheim in the west and Jotunheim in the East...
I think replacing Ulm would be fitting, as this nation seems to have strong army but be weaker in magic/priestly power. Sanguine Heritage can be modded to summon *new unit*, limited only by modding tools and (my?) artistic skills.