[Nitram Draw]

I think there is suppose to be a minimum population to operate one facility but I don't think it works. If there was a minimum population needed per facility that would give a big incentive to move your population around. It would also take a lot longer to get the full benefit of a new colony. As it is now I don't think there are any negatives to low population, just lower bonuses.
It is odd that a new colony builds facilities almost as fast as your homeworld.