How about every RC is associated with an estate. Also, you could have only one RC in any estate. Every region (with a lord) could have at least one, but if you want to keep all those fancy centers online, you need to have a vassal looking after them.
I think its a bad idea for several reasons. First, the lord pays for it so why would the knight get control over it. Second its not realistic and it doesn't add fun/make something better to counter the unrealism. I see no way this will make it anymore fun or better in anyway.
