I propose they add Stargates to the game--but let them be easier to do than in GalCiv lore, due to new technology. Imagine building something like a giant rings as in Babylon 5, perhaps requiring several constructor modules to get the basic gate working. Traffic would be two-way. One option would be conservative: each pair of Stargates only work with each other. Another option would be more liberal: any Stargate could connect with any other gate controlled by the same race. 

Perhaps more modules / higher techs allow access for larger hulled ships, or higher capacity fleets, or decreased transit time. Transit time might be several turns, but on an Immense map it would be worth it. This would radically change strategic movement on really large maps. Creating and defending stargates, at both ends, might become a major issue. For an aggressive race going for a conquest victory on a gigantic or larger map, stargates would be extremely helpful in moving reinforcements to the front lines. For a defensive race, destroying an invader's new Stargate near your territory would be a key strike target. 

Think of the many strategic possibilities with Stargates that allow extremely long distances to be covered in a few turns. Yes, there will be balance issues and details that would need to be worked out, but I hope the developers will give some consideration to adding player built Stargates to this great game. Anyone else want Stargates?