I have spent nine of the last 15 years in the field and find that I hate carrying any extra weight. Really slows me down, but I am skinny and a wuss.
I recommend that you look at the pistol pouch that The Wilderness manufactures. It comes in some different lengths. I lash up two 1" quick release nylon web straps. The first loops over my shoulder, the second around my abdomen. So I wind up with the pistol strapped firmly cross abdomen on me. This keeps the rig out of the way, discreet and protected, yet not too unaccessible. You'd probably have to monkey with the set up with a full pack
With the above rig, I don't need to partially lift the rig each time I tromp with my right leg, like I'd have to with a thigh holster.
I have a Dan Wesson that I dearly adore, but I have to say that if I were only anticipating needing the handgun for last resort protection against humans, I'd carry a Kahr P9. Compact, lightweight and points fast. Any of the plastic framed autos would work well.
For me, 240gr bullets add up too quickly for extended backpacking in mountainous terrain.
FWIW, I work in the same office as a guy who did his Master's thesis on non-lethal deterrents on black bears on Prince of Wales Island in SE AK. After juicing bears with pepper, bean bags, bird bombs and the like, he concluded that he doesn't trust any of them.
FWIW II, pepper spray is not recommended for deterring black bears (at least not on the Tongass Forest).