In a lot of places, a 4-5" 686 or GP100 in .357 magnum is probably plenty of gun. A polymer-framed high-capacity semi-auto in 10mm would be great. Heck, a .357 Sig with hardcast or copper solids could work in a lot of cases. All of those options offer reasonable power and can be reasonably carried.
I wouldn't commit to carrying anything bigger or heavier without a specific risk that demanded it for a particular outdoor area. The biggest threats I'm likely to face are people, followed distantly by black bears, moose, coyotes, snakes, etc. There have been days when I was already carrying a full-sized gun in .40 S&W and decided to go for a walk in the woods. Did I stop and say "is this 165-grain Critical Defense going to be enough"? No. I just enjoyed my walk.
