My thread on horde mechanics:
https://forum.paradoxplaza.com/foru...chanics-ideasgroup-buildings-bukhara.1048624/
Includes horde raiding (also suggested by oim8) a great khan system for mongolia (co-developed with jkiller96) and a mechanic for keeping a horde nomadizing or working it towards a settled state. And some more (read the whole thing as parts of OP is outdated)
Manchus I haven't dealt with much in the horde threads more than the set-up a bit. Yeren should be split, with a new Beishan tag representing Daurs, Solons and nomadic evenks, with Yeren representing semi-settled and settled people in the lower Amur. Both countries should be Siberian clan councils.
Though I get what ppl mean with manchus not really being hordes I don't have any comments yet
Talking terrain, this is an issue with also forest khanates like siberia and kazan, later which ahistirically has steppe land.
Maybe just remove the terrain penalty?