Ghosth! If the CV couldn't leave port until it is all up, that would be a way to keep CVs down an unlimited time and never really have to take the port. All we would have to do is have someone fly over and kill one item to keep it there. Then get the people/effort, take the port and you get the CV at the same time when it pops, if you can get everything back up that is. I can see how this could hurt everyone and make a lot of people mad.
Look at the way Carrier Groups were in the war. Many times they would still have workmen on board to finish a repair while the ship was at sea. That being said, I think, IMVHO, sending a CV out with some functions down would make it interesting. When you came across an enemy CV, you would never know if it was full up or missing troops, ords or had limited fuel.
Another thing to think about. The support ships. These would be troop ships, tankers, etc. Why not sink them and limit what the CV can and can't do? IF you sink one, you would know it was down, but not which one it was, so you wouldn't know if you got the troops, ords or fuel. You could have a listing for the CV just as with a base. But then you(an enemy) can't see the CV on the map. The country could see it and send in supplies.
So, in short, I guess what I'm saying is the CV system needs a complete overhaul with a lot more options. Could you see dropping supplies on a CV for parts to repair and keep planes in the air, or even to repair the ships themselves?