Thanks for the answers so far! About kingdom sizes, what you say makes sense, but it's all very vague in the rules as far as I understand it. The size a fiefdom covers isn't really detailed, and neither is how the number and size thereof corresponds to your size on the actual map. Like I could circle a huge swathe of land, but only divide it into like 3 or so fiefdoms, or in turn, I could claim that tiny island in the north and have about 20 fiefdoms or so on it - and the fiefdoms should, in theory, operate with the same efficiency regardless of their span on the map. Sure, I'll try to employ common sense, as should anyone, but it's got me wondering a little on how to handle it, particularly since the scale of the map is also pretty vague (having a scale indicator in a corner would be helpful in that regard).

That's an interesting detail about the church being a splinter group. With then owning so much land and power, I imagine they are still kind of like a substitute for the vatican in this RP, and it's not far fetched to think that they would treat faiths that are entirely apart from their divine canon as pagan heathens.