I really like the simplicity approach in the architecture, most maps nowadays seem almost overforged. The only problems I see are that having the cave as the only route between bases means you'll likely end up with a basic chokepoint, and it won't offer much variation in gameplay or tactics. Also, the map seems like it'd be a pain to navigate on foot, and if the vehicles are occupied or destroyed, it'd be annoying to have to trek all the way back to and through the cave just to get back into the action.