Quote Originally Posted by The King View Post
Is it wise to build one from each of them into the county if it is possible? So far I have tried to have 1 from each of them.
Typically I find it pays to have one castle and the rest be cities, with possibly one bishopric.

The income boost you get from cities far outstrips what you get from castles. Since battles are mostly about numbers and commander skill, having the high-quality troops of extra castles doesn't really make up for the fact you could be using the extra money from extra cities to just hire mercenaries if you really need them. And if you don't need them, you can use the money for other things, like building more cities and getting even more money.

The only place a castle might beat a city is in a landlocked area, like HRE, Hungary, or Russia.

I wouldn't ever build a new bishopric, personally. The ones you start out with are good in the early game, but by the time you actually have the spare cash to build new holdings, you are likely far enough along in tech that they start to become mediocre compared to the other two. Also, bishops don't have to pay you anything or give you any troops if they don't like you, so there's that.