Well, I don't worry so much about zombie ninjas out in the woods. I guess theoretically you could stumble upon a marijuana patch or a pack of mojados with their armed coyotes or banditos hauling cocaine or something, in theory, never knew it to happen to anyone I knew, though. Getting a lot rougher down in the big bend area now days, though, and hell, I might go for the firepower along the border now days. Yeah, I'm a little more paranoid down there. I worry more about 2 legged critters in the concrete jungle, a lot more, but you could run into deliverance I guess and, hell, it made for a good movie even when all they had was bows.
I can see the value of an autoloader in the bend, though, I mean, since I can't carry a SAW legally down there. That's a whole nuther situation.
A cat or bear is going to be on you so fast, that magazine full of ammo is going to just be dead weight. I doubt you'll get a second shot off. You might not get the first one off, especially with a cat. That, too, is very low risk IMHO.
Anyway, I have much admiration for the ballistics of the 10mm, but like you said, it's a platform thing for me. In the outdoor roll, revolvers rule with me. Too, if I'm going to carry a G20's weight, I'd rather be packin' my .45 Colt blackhawk pushing a 300 grain bullet to 1000 ft lbs. Why not? I agree, though, I've always preferred a lighter gun in .357 magnum if hiking or back packing. Don't need .44 magnum power where I have hiked, nothing bigger than black bear and cats. Either the 10 or the .357 will do fine and on humans, the same. The threat leave is so low doing such activities, though, I feel light is right. A 3 to 5" M60 with adjustables has always seemed like it might be ideal for such, though I've carried K frame 4" guns with no problem. I do like having an adjustable sight just so I can set the sight for .38 special if I'm looking for camp meat. As good as the little SP101s are, their sights are fixed.
Ya know what? Just thinkin' about it, if I ever go back to the bend, I'll just take my P90. It shoots nearly as good as a revolver, about 1.5" groups at 25. Only thing, a 10mm shoots a lot flatter out in that open country. Supposedly, Ruger was designing the P90 for the 10. If they ever come out with a P90 in 10mm, I think I might just be a customer. It'll never happen, though. The old style P guns are off Ruger's radar, it seems. I won't consider a glock for several reasons. First, they don't shoot lead without an aftermarket barrel and I won't own a gun that won't shoot lead. I cast, it's what I do. That's enough to keep me away from Glock and there are few other 10s on the market that aren't HUGE or 1911s and I consider the 1911 not quite enough gun for the high pressure 10mm loads, tough on those guns.
BTW, I like to keep my iron sighted shots on deer to 50 yards with .357. I can hit 4"-6" groups at 100 yards all day at the range off shooting stix, though. I amaze the rifle guys sometimes. My cheater gun, a 12" Contender in .30-30 has a 2x scope on it. I can group that gun 3" at 200 yards off sand bags and have taken deer to 90 yards so far, which is a long shot out on my place being as it's mighty brushy. Very simply, the more accurate the gun, the more confident I am with it. Confidence means a lot.
