Re: Space to spare
"I have several boxes of paperbacks I'd like to store somewhere secure. If the MOD/Navy want, I could store them in a corner of all that unused hangar space."
This is about the only sensible use of the things.
Carriers need a "carrier group" escort. The UK doesn't have enough ships to make up ONE carrier support group, let alone two.
Without a carrier support group, these are HMS Sitting Duck and HMS White Elephant.
Even with them, given the huge amount of bunker fuel onboard and the existence of anti-ship ballistic missiles (ASBM), the names are probably appropriate.