There is plenty of good sci-fi roguelikes, but not much that got space-sim approach. You could check Transcendence, it's enough roguelike-ish to call it roguelike, especially in these times... There is some more projects like ASCII Sector, bust most of them is underdeveloped, thought.
Wild west is still mostly unexplored by roguelike developers, but Land of Strangers is a good one.
edit: just checked, official download links of Land of Strangers are broken. Do you know something about that, Aging Minotaur?