Drink Your Wine
A square arena, with a ledge around the outside and a raised square fortress in the center. Simple, but well-designed for flow. The hill (The central fort) is accessible from both the ledge (via a bridge) and the bottom (via a fast elevator). There are a few pillars to use as cover... but more than two people in the game, and staying on the hill is a non-trivial excercise.
Levels in map "Drink Your Wine":
Drink Your Wine