A combination of first person shooter and real time strategy. There is a large map and balanced units on each side. Each round, a team commander is chosen randomly from each team. During play, the commander sees a bird’s eye view of the current battle and directs player objectives, waypoints, etc. while everyone else is playing COD-style first person (trying to take advantage of the intelligence and goal setting from the commander). “The game” is sustained over many rounds, teams taking and losing ground as individual battles are won and lost.

I haven’t thought deeply about how much RTS complexity would be appropriate - but you would want to keep the action symmetrical so nobody is ‘waiting’ around for decisions to be made.