I think a space station would be perfect for new content; there is just so much you could do with it. Maybe at one end part of it has been sealed off because an explosion that tore into the station, then in whatever level you first encounter it, you could have to go out and have ghost analyze something... and a hive tomb ship comes and you can see it dropping off tons of enemies, which you get to fight using the z-axis (more floating). There is just too much great content you could make from this, maybe even a new enemy class of its own. (Not expecting this though)