TBH, I don't mind. I personally like this kind of theme because I'm a fan of Sci-Fi. It would be so cool if they add in a different alien life state, something like Spore or Chewbacca or Yoda as the NPC. I'm not a Star Wars diehard fan, but that's kind of movies that will make me go to the cinema.
More than anything, since it's something that the developers never done before, I'm more intrigued to learn what kind of "crazy" idea that they're going to show it to us.
Though, it's understandable that some Simmers prefer realism, but we should embrace realism & fantasy. Just my 2 cents. ;)