A good late game tech would be to be able to make the less quality planets settlements.The higher the tech the lower quality planet you could put a settlement on.Settlements could resupply ships or you could have say a scientific settlement that would give a little boost to research but could also have the possibility of producing anomolies,(an experiment gone wrong perhaps), like space warps to get your ships around faster.It would also give you a reason for designing better colony ships since usually in a galciv game most of the colonizable planets are gone in the beginning.