Orange, have you personally shot any bears and seen that result? If you look at the test data done by the military and the FBI, 10mm isn't really putting THAT much more energy into the target than any of the other usual suspects caliber wise.
I shoot 10mm as well, I have a Delta Colt 10mm and a couple Smith 1006's, and I like it as well, prior to the 357 sig coming around, it was THE high velocity auto cartridge to shoot IMO. That said, again, it isn't leaps and bounds better than anything else, not a single caliber from 9 to 40, 45 357 etc has an edge larger than 10-20 percent over anything else. If that with premium ammo. 10mm with good loads moving at 1250 will usually be over 600 ft/lbs, compared to around 400 with really good 9mm ammo. This still isn't anything to write home over IMO. Many people consider 556 to be a poodle shooter, yet a typical NATO round has 1700 ft/lbs of energy. See what I mean?
Velocity is the most important factor, followed by bullet weight, then caliber/size/etc. Having a 130 gr low velocity, ie subsonic 45 round would be a terribly poor performer. 850 ish feet per second with 130gr bullet, it doesn't matter if it's 9, 45, or 75 caliber, it won't put enough energy into the target. A 115 9mm going typical defense load velocity will hit harder, far harder than that will. I get your idea smoe, but it's physics, unless you use some sort of expanding or exploding round, velocity is the critical component to lethality. The 5.7 which is essentially a .22 bullet going warp speed is one way to go, the opposite way to what you're suggesting, high high velocity with light weight projectile, and it tends to be more lethal than very low speed mid weight rounds. There is tons of data out there for certain to look at.