I dunno, I kinda like the number idea, it's only indoor CQB afterall, not like it's milsim anyway lol
Most people have distinguishing features, but a lot of noobs don't, big numbers might be a good way to keep track of people. Maybe just armbands or whatever.
I like the idea of keeping track of complainers though, I've known more than a few players that swear up and down people are cheating and they see BBs bouncing off their target, but upon further inspection it turns out they can't even see their BBs and they're all falling 15ft short lol
And not to brand people, but the guys at XT know there are certain groups of people that are quite prone to cheating, so those groups usually play together and anyone else that wants to join in is given plenty of warning about it.