Understand but remember there were 5600 + Mk IXs and 1054 Mk XVIs, many built in 1944/1945 when they werent always needed. Mk Is - "only" 1500 + built and survivors had to survive at least from 1941 onwards. The population of "available" MK IXs & MK XVIs for restoration is higher so there will...
Wildcats, Corairs & Hellcats were built for carrier ops - by design they had to be rugged which carried a weight penalty. Spitfire & 109 were designed as interceptors, power:weight was everything, time to altitude & manouverability were key inputs - not so for the naval fighters.
10G ? Modern F 16 or F 35 are "only" stressed for 9 G. Doubt a pilot could survive any routine 10 G manouevres.
Spitfire was one of the strongest airframes (particularly the wing) in the early war years. P 40 ... not aware ..
I think the French used Spitfire Mk IXs early in the "Indo China" war. If so these would have had metal ailerons. Maybe also Seafires ? The French never had 2 seat Spitfires so I think this part is not correct.