As far as rapid fire confidence, that's why the 1911 is so devastating as a rapid fire platform. The heavier design tames the massive recoil to that which is somewhat less than a Glock shooting 9’s. You can keep those low grain .9mm lightly built hollow points. They won't provide lethal penetration like the kind needed to produce one shot lethality. Extra velocity won't make up the difference either without Sectional Density or mass to back it up.
Not an argument question but for debate, the FN 5.7 of the Ft. Hood Shooter had a kill rate of 43% in hits. Isn’t kill ratio dependant on shot placement and projectle mass and speed?
Only asking.