I can only say that putting a cap like this will completely destroy a huge aspect of the game for alot of people - and will without a doubt kill of part of the community. This is mostly people who DO NOT rank and only enjoy doing random premade vs premade games in the weekends.
 
	It is a horrible fucking idea to even consider - and even just testing it out will permanently damage the server. 
 
	 
 
	Reconsider and take a step back before you do something you really wish you did not do. Truth be told you will be removing this cap eventually if you do implement it - only thing you will have succeeded in doing is make a part of the community quit, making afking/botting in bg's more regular and generally damaging the server.