With the ability to manufacture all sorts of ships at player colonies, I often find that while the fleet loadout is easy to change, it is difficult to make fleet changes because officers as stuck in particular roles of either battleship officer or carrier officers.
With player owned colonies, I think officers shouldn’t need to be fired to make room for new officers in the fleet. I think once the player gets a High Command building going, he should have the option of putting unneeded officers into desk jobs at the admiralty, at half pay, and have them generate “command points” or something to set up planetary invasions, or level up through simulator training.
This is mostly to facilitate quick switching from combat centric fleets to carrier centric fleets, and it is also realistic, while there is nowhere for an idle officer to go at a marauding fleet, there would be plenty of jobs to keep them busy at a large colony.
“Okay, carrier battlegroups is the way forward, but don’t you battleship gurus go look for that freighter job just yet, we might need you next year, so sit tight and work on that well paid desk job.”