I'd make some sort of mmo (rpg or a mix of fps/rpg, a la Neocron) in the Blue Planet setting.
Blue Planet is a very not popular space opera/cyberpunk pen & paper rpg. Of course, it would be the best game ever since it's my idea, so let's not waste time going through all the features.
I'd follow with a massively multiplayer Mario Kart thing, since by then I'll be totaly out of new ideas like every game studio out there after its first hit. Maybe buy the Wacky Wheels license (is there such a thing?).