I think issues like whether or not to have tactical combat are central to the question of "What kind of control does GalCiv (whatever version) want the player to have?"
I've always looked at like this: The name of the series is "Galactic Civilizations" not "Galactic Planet" or something similar. Which leads to the concept of "Yes, you can micromanage and min/max down to this level. But below that level you have little or no control over how things resolve."
ForgottenSlayer's point about "if the feature is there, everyone would use it" goes back to the Planetary Wheel that used to exist in GalCiv3. You could tailor the output of any of the planets you owned to a totally, ridiculous degree and a lot of players spent ages moving pointers, etc to get 500 Production Per Turn (or even bigger numbers!) from their Manufacturing World or whereever.
I think Stardock have given players enough "min-maxing"/scopt to make things to their liking to the nth of the nth of the nth degree with things like the Ship Designer. I get the impression from things Frogboy has said over the years that he's well aware that too much min-maxing takes away from the core of what 4X/GalCiv is.
That said, I think there's a lot more scope to GalCiv combat than just "In Turn 25, the Drengin and Terran fought in the Sol system. In Turn 26, all the Drengin were dead." I've advocated being able to set up fleets like the bots in Gladiabots: "If Ship Health > 25% Then Withdraw", "If Nearest Enemy Ship Health > 25% And Nearest Enemy Ship Health > 25% Withdraws Then Ship Pursue" type logic.