Arena play doesn't get more straightforward than this map. Ledges for sniper shots, what appears to be a crusher in the middle but no luck in activating. No rechargers, no frills.
A Quad with multiple upright pillar-type thingys to hide behind and some really mean spirited Troopers; this should satisfy two players easily, probably three would be okay, four would be a crowd.
Arena-type setup with a circular reservoir in the middle & Big Blue standing on top pegging shots at you. Fast. Shooting at him may cause your weapon to backfire!
Large inner circle with surrounding stairs leading off to four corner rooms/areas where weapons & ammo can be picked up. Stairs for ammo also. Central area of circle continually raised Compilers upon entering, only alien to be seen. 2x canister. Probably would work as KOTH or tag.