Are you thinking of limiting buildings per estate by percentage, number of peasants in estate, or some combination of the two?
Basing it on # peasants is too silly. I honestly hate how BM handles population and I hope it will be completely overhauled one day.
I think this should be based on percentage. You start off with 1 free slot. For every 5%, you get 1 more slot. So there is actually some incentives on being a goddamn rural knight over a city knight for a change.
