Hey Steelheart! The base assumption is indeed fantasy but we've tried to be as wide as possible and we did space colonies and cyberpunk cities in our playtests. Since terrain features prominently, it makes space stations a bit difficult but with some imagination I think you could make it work.
As for the wild west: I think the only thing that really needs some changing is the terrain table. It is broad enough to encompass a WIDE VARIETY of places, climates and terrain. You could either create a custom table for your setting OR simply reinterpret things accordingly. So if you're set on a dry savannah climate, a result of "swamp" would maybe be a patch of more lush vegetation but no real wetland.
In any case, if you're interested you might want to grab the game quickly before the sale runs out.