But you also build up industry, organization and experience, both in building up and handling large air formations.A few points
Building an air force in the early 1930s means building a lot of obsolete by 1940 so nuts to that.
Regarding Singapore, I am not so sure it was a folly to build it up as a fortress. Percival's performance has been heavily criticized, the author of "On the Psychology of Military Incompetence" even it used it as a case study for his book. I wonder how things had developed if Singapore had been competently defended.
Regarding the HMS Glorious, something that baffles me, was it really normal procedure to send an entire aircraft carrier away from the front back home because one officer needs to go to court-martial? It seems rather wasteful to me.