I asked the same question today on twitter and I got almost the same reply: sometimes EVIL choices can be taken but in general people prefer to play as GOOD. I use the same approach.
I was asking because I was thinking to offer some sort of evil endings / choices in Planet Stronghold sequel, but on the other hands if they would be very unpopular... doesn't make much sense. In the first game there are many "grey area" decisions, like when you can exterminate an alien race or destroy their places of cult, but in the end you're always a hero and not an evil tyranny or something like that
