Great game. I waste far too much time playing it.
That said, and fresh off a Normal/Gigantic game (on the latest beta release), here two small "nice to haves"; if they reflect something I've overlooked, my apologies in advance:
* It would be nice to have TAB/ENTER control for pop-up boxes/windows, so that you could get rid of them w/out having to use the mouse. For example, when the "Do you wish to update this starbase?" box comes up, have the Yes button selected and have activate it; let the user hit to cycle among buttons. (That would also make the anomaly popups more tolerable w/out having to turn them off altogether.)
* It would be nice to have a means other than the slider for transferring people into colony ships. Late in the game, the systems creating the colony ships often have 40+ billion inhabitants. That makes it hard to put less than '2000' (that is, 2 billion) people on a single colony ship--and having too many people has a dramatic impact on morale when colonizing. True, you can click on the arrows at either end of the slider, but that changes the value only by 1--a bit tedious, if one wishes to set the value at, say, 800. Perhaps the arrow clicks could be made proportional to the total population; for example, if the system population is 40 billion, then each click would at/subtract '40' (million), but never less than '1'.
For what they're worth. GalCiv really is a well-done game; my congratulations to all involved.