I guess I'm not the first one with this idea, but I imagine how beautiful a mode called "CTF" - a simple capture the flag game, would be. I regret that I have absolutely no know-how in making modes, but after I saw how fast the mode "Jailbreak" was developed, I hope somebody who is able to do this, want to try it!
A good guideline could be warzone from wow. Its rules would fit also great in my imagined mode.
> 2 teams, 2 bases
> get the flag from the enemy's base and put it down in your base, while your own flag is there
> if the flag carrier is shot, the flag drops where he dies
> the flag can kept again by one team, to score by bringing into the base
> the flag can brought back to the base by the other team, when they touch it
Detailed rules can be made then, things as
- how much points each team needs to win
- how much flags can be carried at the same time
- 1 or 2 hits to kill
- ... and so on
I hope, I posted correct in this area, I hope, i didn't steal somebody's idea, and I hope some good guys will come here together to create a great game mode!
So... have fun

Dimrain