The size of the primer pocket has as much to do with the strength of a cartridge case as the size of the headlights on a pickup do with its horsepower.
The .40 case is too short to safely load a 200gr bullet in without bulging the case where the sidewall tapers and also results in too small a powder capacity to use AA9, blue dot, Power Pistol etc. for effective velocity at safe pressures.
Also, don't forget the Glock is marginal on strength to begin with and the 40 models are all built on the small 9mm frame whereas the 10mm is on the large frame built for the 10mm to begin with.
If you want to play hot rod with a pistol cartridge that pushes close to 40,000psi I'd strongly recommend something with an all steel frame, fully supported chamber and an extra margin of safety such as the Witness or even the 1911 types from Dan Wesson etc.