This may be an unrealistic idea but ive always wanted a major revamp of minmus, first there could be a breathable atmosphere that stops at a 1500m from sea level? Second there could be salt lakes in the salt flats of minmus, 100 meters deep but extremely buoyant. Third there could be a thin ring orbiting it at a 45 degree inclination and finally, a moon half the size of gilly, but twice as dense as minmus mabye?
heck call the sub-moon minminmus