My favorite Space sim was IWar2 : Edge of chaos. Playing that with my MS SW FFB 2 joystick was awesome. Great story, great flight model, piracy, trading. A modern version of that would do me fine.
I played all the X Games, but I have grown jaded by the fact that its more of a factory management sim than anything else. I like to be the lone trader/fighter in a small craft with an incentive to upgrade and explore.