Sins is not Civ4! It's a lot easier to add features within the framework of a turn-based game than it is in a real-time strategy game. Why do you think Sins is the first (and only) respectable RT4X game? (Empire Earth tried, and I've yet to play III, but from what I saw in I, II, and the expansions, it never really created a true 4X feel as Sins does)
But yeah, I liked being able to rename fleets in GalCiv2. I would always name them after the system they were based in, like "Battlefleet Terra" and so on, to keep track of them better.