Right now the map lacks East Asia. I'll add that later, if I have the time and the energy. But right now I'll focus on the existing areas.
Anyways, I had some thoughts about Hyrkania. Usually Hyrkania is depicted as a Russia-like kingdom that lies between "Europe" and "China". However, my impression (from the close reading of the Hyborian Age essay) is that the Hyrkanians began on the eastern shore of Asia (modern China) and pushed westwards till they reached the Vilayet sea, stretching across the continent. Basically I see them as the Hyborian age equivalent of Gengish Khan's empire.
However, such an empire would be incredibly powerful. It would have as much IC and manpower as every other country combined. That wouldn't be very fun. So maybe they could an event in the beginning of play which would say something like: "We're a huge multinational empire and blah blah blah, so it's difficult to run such an empire."
Basically, only urban provinces would be national provinces. Others would have a chance for revolts. Hyrkania would still be extremely powerful, but they'd also have to worry about partisans.
Hyrkanian City-States (Turanian puppet on the eastern shore of the Vilayet sea) would, likewise, only have national provinces on the titular city-states. However, they could also "declare independence", i.e. revoke their puppet status. In such a case Turan would declare war against them, but they would also get national provinces and free units ("Tribes unite" or similar event).