European maps will have natives, but as far as I know they are just going to be generic professions, like Miners and Lumberjacks, rather than actual nationalities.
And if we tried to include every single people group in the world, stateless or not, even just as native sites, there would be inconcievably too many. It's simply not possible, so difficult decisions have to be made about whom to include and not.
The Czech War Wagons, despite being anachronistic for this mod, are available from a Habsburgs HC mercs card.
Sure, hundreds of cultures or ethnic groups are pointless (tho it would be extremely cool to have game with hundreds of different homecities
). But how about some compromise using criteria like Nation history (some nations didnt come out of nowhere but they were part of the other state while keeping their unique language, culture, techs etc.), size of nation/state here and then (some tiny nations are already used as units - Kalmucks, Baskhirs, Cossacks, but some bigger ones like Poland are huge and real now... ), uniqueness (some nations may have their own unique soldiers, technologies, religion).
It may sound selfish, but i care almost only about Europe. It had relatively stable ethnic groups and its history is well known compared to f.e. Africa, America... and maybe Asia, but i am not very sure there. Dunno what plans for mod are, and if you want to reach the some official finish line when you say "we are done here". But if not, sooner or later you will run out of civs and then, If you chose like 5 biggest/most important/most independent civs, i would be more than happy.
Now i feel like an idiot forcing people to do something for me in their free time... i hope you take it as a suggestion for feature you could also enjoy :-)