here is a neat idea for a part, a xenon scoop that you could unlock shortly after the dawn engine that would deploy like a solar panel and collect very small amounts of xenon, enough to keep it running almost indefinitely. if the game ever went interstellar this would be a low-tech - relatively speaking of course in comparison to warp or near ftl - solution to rudimentary exploration of worlds beyond. another feature that would complement interstellar nicely would be a fog of exploration, like in sid meier's civ, where you could only see within a certain range of where you've been.