I like the Diverse trait too, even though only for the races. Like, no UU of outside. That's what I mean to do in my own mod (maybe you were thinking I was going to do it like in the TweakMod, Valk?). I don't know how the race is chosen in the TweakMod but I plan to do it function of the surroundings of the city. Forests->Elves, Hills->Dwarves, Jungle->Lizards, etc. However, I still don't know if it will be for the Kurios or for the Grigori. I'm thinking lately that the Grigori are more in "need" of a new mechanic than the Kurios...
As for the worldspell idea Valkrionn is talking about, see
here.
Also, I gave them the Humanist civ trait, making them agnostics (opposing uniqueCult/Intolerant leaders, which is an innovation of my mod too) and giving them access right from the start to the Humanism civic.
(I didn't read the whole thread yet, only the last page
)