Well, since the best ideas are here....
1)How bout a voting system? Since the admins can not always be available, it would be nice to boot those obvious cheaters, like $Mr.Verceti$ that drive on water while advertising they are going to do it.
2) Teams! yes I like the team color Idea where the name shows color.
3) Max ping/quality I know this might be hard at first with the netcode still needing tweaks but would also help reduce accused cheaters that really are legit.
4) A way to make multi server type games. This is probably the hardest Idea, but if you could have a server program that would allow a server for each section of town, then maybe lag/packet loss could be reduced. There would have to be small neutral zones where people couldnt shoot be hit when transferring from one server to the other. (probably not the best idea but would also help in allowing custom maps?)
5) time limits. It would be nice if there was an option for admins to set time limits on the game. This would work best when te game is made more team oreinted.
6)This one kind of needs idea 2. Like the above, a server has choice on turning team damage on, off, penalty. If set to penatly, when a teamie shoots another teamie he takes the same damage as the victim.
7) This one might be there already. The server should log IP's to names so admins can ban ip's when people report cheaters. This would work best with the max ping/quality again to help decifer whos a cheat and who is laggy.
8)This one is more just to help those little racists from becoming a pain. A chat filter. Tonight I was in a game and this guy was a racist pain in the arse. I didn't take the abuse, nor did I fit the category, but some things just don't need to be said.
9)Me to stop posting suggestions for a while I have alot more ideas, but I think the devs have their hands full as it is