I've been kicking around here for a while now, and had somehow missed this thread. Great content, great discussion, and gorgeous pics. Thank you for sharing with us!
TBH, my "work guns" were chambered in 5.56x45 or 7.62X51....but I will say that your choices and their evolution have somewhat mirrored mine once I moved to civilian life, although with different applications, no ATC, and nowhere near the street cred. To this point a bear has not been on the list of mammals that I've ended up shooting at - the truth is that a moose near Rocky Mountain House is the most threatening large wildlife encounter that I've had.
I started out with a short barreled 870 for bear defense when fly fishing or enjoying other recreating in griz country. Then I moved to Texas, and ended up using a Glock 20 (with a light and Trijicon HD sights) as my backup when hog hunting. Having a potent load available in a pistol suitable for use in the dark is a very good idea in that part of the world given how thick the brush is, the fact that hogs are nocturnal, the potential for even a medium sized hog to cause significant physical harm to a person, and my own desire to ensure an ethical harvest. I can happily report that a 180 grain FTX at 1300 FPS had a 100% effectiveness rate for me when called upon to make a pig stay exactly where it was. I'm still a big fan of the 10mm...but obviously I no longer carry one when afield.
Since I've moved back to Canada, I've changed over to a Steyr Dragoon Scout in .376 Steyr. That rather eccentric cartridge is by no means equal to the .375 H&H that you are fond of, but with a pile of powder behind a 270 or 300 grain pill, it is not far behind and is most definitely into "suitable for dangerous game" territory. It also has the benefit of having ballistics that emulate the .308 loads I use in for other hunting, easily mounting a light under the stock, and being both light and handy enough to be very handy when elk hunting. As an added bonus, when downloaded with 225 grain soft points over a moderate powder load the terminal ballistics are a lot like a stout .30-06 load.
