I found the way they did the Diversity in Wheel of Time to be a bit odd, everywhere, from Cities to hick mining towns seemed to have the same mixture of different races as if it was calculated out on a spreadsheet. Didn't really make sense within the history of that world( apocalypse scattering people into isolated communities with little interaction outside of major trade routes or organizations that drew from disparate areas, the Aes Sedai for example should be massively diverse as a group) Think it, along with some other decisions led to poorly established world building, scale, and a lack of distinctly different cultures in the new areas that the story should take the viewer. I know there some of the usual complaints about the 2 Rivers folk but is actually quite ambiguous in the books, the only thing that really needs to be there is the actor for Rand should look strikingly different to the rest of the group.
I thought that was one of the most interesting things about an adaptation, how they would interpret all these different cultures, and outside of the end scene of season one there was little to feed that interest. Hopefully along with all the vast other improvements needed they can step up there as well.