This sounds like a really interesting project.
After experiencing a little high frequency hearing loss while hunting geese (it was in the winter & my stocking cap somehow interfered with the seal on my electronic ear muffs) - - I've been very aware of the effect of gun blast. Its pretty tough to hunt or be at your best in a defensive situation, if youre deaf.
Among my favorite handgun cartridges are the 45 Colt and 44 Special because they get the job done very well, without a lot of blast or fuss.
I look forward to your results.
P.S. - - it would be interesting to test some ammo advertised to offer lower flash and blast, to see how they actually measure up. I like the Speer Gold Dot 45 Colt commercial load. Modest velocities and muzzle blast - but they open up at slow speeds and penetrate well.