beside the building race game mode, the defend your structure game mode and steal capitalist game mode.
make a map where u can make a race give map edges cliffs and structure to block. the point is the player to have a special unit like a structure a flag or a special tank. and your opponent stops u to arrive at your destination. there could be 3 modes one for air, one for tanks and one for boats. imagine making a map 16X16 and the map put's u on the opposite side of your enemy 1 vs 1 u must stop your enemy from getting there. u use your army to advance but if your enemy destroy your flag unit u lose but u must be fast. your opponent can build whatever defenses to stop u from arriving. u build whatever fast units to accompany your special unit. lets say like a your commander bot scrapped that make your commander bot arrive at the location and your enemy loses ;D.