Can a mod limit castle construction?

[Xietor]

What can he do? He still gets all of his gems, and in the endgame, most of his army is summoned beings(:

Also, to win you need to take provinces, kill him off, and move on to the next nation. However, I am appreciative of all the endgame advice.

But my primary goal is to make the endgame move quicker-something most veteran mp's agree would be a good thing. Less castles would go a long way to achieving that goal. Though it seems another avenue may need to be found since a mod cannot limit castle construction.