Love.
Honestly, though, I'd rather see Galciv gain all the good features of Moo2 it lacked, or Moo4 gain all of Galciv's good features. Honestly, they're both 90 percent perfect, I think with some sleectiove editing, someone could make 110. (It should be impossible, but it isn't!!!)
I'd like to be able to assimilate other races into my multicultural empire. A race if scientists with a science bonus, farmers with farming bonuses, a caste of powerful alien soldiers, be like an evil Federation. Be able to capture and board enemy ships, and have total customization over my race being a cyborg, destroy planets or create asteroid belts, or turn them into new planets. All the neato stuff from MOO2. Only, maybe with Galciv's excellent AI, random events, anomalies, bases, and customizable ships.

I'd personally pay lots of money for this. Lots.