[Kagetora]

Yeah but the ringworld costs 500K of each resource and the sphere twice that much not counting the cost of the shipyard ships or the cost of the facilites. Not to mention all the population you will have to skim off to populate them. It would take alot of production just to recover the cost and you get no bonus for production over 10B pop. So really the sphereworlds are not at all worth building over a ringworld at half the cost.