Hmm. I like most, am neutral to some aspects and very much dislike one.
I mean, oki. It costs a lot of credits. So an active fleet can rise it, the solo player can also if he spends a lot of time VO mining. Fine enough. Moving it requires a grind of some new ressource. So for a fleet, it's 30 minutes (numbers completely made up, but it sounds accceptable) of collective work, a solo player spends two evenings to be able to move his carrier. Fair enough.
But why would it be locked to the commander? I mean, i get it: we currently have no way to transfer credits between commanders. So yea, one commander has to earn the money and buy the carrier. But why not have fleet/squadron donations? I would expect that to be in place for the fuel resource, anyway.
I mean, with a donation system all players of a fleet/squadron can donate credits to buy and upgrade the carrier. All players can each week donate some jump material to keep things going. But then the carrier should also be locked to the fleet/squadron. I mean, it still won't help preventing a malicious person to run off with it. If he leads the fleet, he can still have everybody contribute to his ship, then kick them all.
But there's one other important aspect: players come and go. (For plenty of reasons, anything from being bored and burnt of the game to death. ) Fleets/squadron endure. But it would be all to bad for a fleet/squadron if the guy with the fleet carrier disappears.
If the carrier is locked to the fleet/squadron the problem doesn't exist. A little bit of reorganisation and the fleet/squadron can just carry on. In my eyes it's the much better solution and it also doesn't hurt the solo player. (The solo player simply creates his squadron of one and gets his carrier. Nothing lost there. )