My game would be: User starts as a marine of a boarding team on a destroyer/frigate type "in-system" space craft. The user can gain rank towards squad leader, then platoon leader, etc on to the ship captain. The player should be able to toggle between ship to ship action and FP/squad level action, to give the illusion of being a part of a larger scene - not just the boarding incursion. The overall environment should be simple; maybe a small system with several planets and one or more stations...