If looking at a relatively small number of hardened combat Marines in need of a close quarter combat pistol, something along the lines of a railed 1911 45acp could be very doable.
If looking at a service pistol for all of today�s army, something along the lines of a modular pistol would probably be high on the list of requirements. You see the same thing today in trends with service pistols for LEO agencies who must equip and train a wide swath of personnel, to include those who may be very small in stature with very small hands. Having a modular pistol platform that is simple LEGO-esque plug and play, to quickly snap on and off pieces and parts to change barrel, frame, and/or grip size, may be the order of the day. In addition, terminal bullet performance may be tempered with the overall recoil of the pistol so that it may be easily handled by the smallest and weakest of personnel. Not making predictions, but current pistols such as the M&P and the Sig-250 are marketed to fit such bill. But in the end, what the army selects as ideal for their needs, will likely be different than ideal for use in CQB by a smaller group of hardened Marines.
