I feel it's a good choice to keep it space science only, because if not, all the players have to do is conquer the easy Neumann V and they get a 50% drain lab!
Compared to the biolab (that also give the massive 50% science drain):
To gain the biolab, you have to:
-Conquer Gleba
-Pay the expensive research
-Setup the biter eggs spoilable
To get the Microgravity lab, you have to
- Land on Neumann 5 with a rocket silo