Desert Thunder on extreme with rushers who does no gates and no a alleyway o.o
Usually finish the game with 12 minute left (8 min in all?) and yield about 150 EXP : 200 GP with just 15 kills (most from nades).
I would say just take turns becoming super spy and uploading intel with some friends o.o
I actually got 1200 GP and 800 exp for uploading successfully.
Or just go afk alot like me and do other things with your life while your character sits in-game not moving. And come back to join a new room and ready up every once in a while...