I feel that for this to work we would need a system where some stability decisions matter more in one place than another. For example, when a civ discovers democracy, all new world cities get hit with a negative stability for state religion, monarchy, and mercantilism. This represents the fact that after america was founded Spain lost it's colonies in a one-two punch of democratic demands of the Criollo class and the capitulation to Napoleons France.
I concur with the opinions of the above post greatly, but the quoted one is top of my list
The only one I could justify of the top of my head is a Khazak khanate. Mongolia would have to deal with both Iran and Khazaks. Add maybe a Ming respawn. They collapsed in 1847, so the 1700 campaign would start with them there.
I know there is much wish for a civ for that region, the problem is the history doesn't allow for many choices. There is the Scythians, who are not a unified nation by any stretch of the imagination (though your imagination maybe more flexible than mine).
The actual candidates then are:
The Kushan Empire (1st Century B.C.E. - 4th Century C.E.)
UHV
1) The Silk Road: Establish open borders with China, Rome, and Ethiopia
2) Multicultural: Build a Stupa, Mandir, and Holy Fire
3) Winter Palace: Build the Qila Mubarak in India
UU: Look
here. Their army had a mix of all things, though they are noted as having both Cataphracts and Tower elephants. I say a cataphract replacement to the horse archer named "Yabgu Guard"
UB: instead of a building replacement, how about a special wonder? The
Qila Mubarak, it acts as a second palace.
The other candidates are all post mongol, and extremely short lived. The two best are the
Bukhara (Khanate from 1500 to 1785, Emirate from 1786 to 1920). And the
Kazakh (14561847)