I share the majority opinion in this thread, i.e. 357 magnum provides all the power you could possibly need east of the Rockies, as well as the versatility of loading hot and/or "heavy" up to 180 or even 200 grains or very mild/light 38 spl and everything in between. The only real question is how light does the gun need to be. Also: Can you open carry in a field holster or chest holster, or must it be concealed? Besides the reasonable (IMO) weight of your J, K and L-frame options, one other argument in favor of 357/38 is the availability and cost of ammo. If you're going to carry a revolver, you have to practice somewhat regularly after all.

My personal choice when I leave the asphalt behind is usually a 4-inch K-frame sporting 180 grain hardcast wide flatpoint bullets. A bit overkill for panther and pesky bobcats, but feral pigs and black bear roam these woods, too. Not to mention alligators where there's fresh water. It probably doesn't take that much gun to put a 'gator down, but I ain't taking my chances either, because they've been kind of ornery in our neck of the woods lately for some reason. Just last week there was a 4-footer hiding in the culvert under a driveway across the street. Something like that would only be dangerous for small pets and kids. But a 13-footer killed two German Shepherds the next town over the other day and would have probably attacked the owner, too, if the dogs hadn't been wandering off-leash. Oh, and then there's all kinds of venomous snakes. My neighbor had a water moccasin blocking his front door not too long ago. So snake shot is a must-have. Snakes may not be an issue where you live, but it would probably be useful for rodents and things like rabid bats, raccoons, etc. Always take snake shot with you at least in a spare strip or speed loader.

I also have a J-frame that I keep loaded with Buffalo Bore 158 grain 38 spl+p LSWC hollow points. That's plenty of bullet for two-legged critters and ought to suffice for black bear, too. So if you settle on the lightweight convenience of a J-frame, you should still be fine. As others have mentioned, a 3-inch model 60 would be a great choice, especially if it's rated for 357 magnum so you at least have the option of "going nuclear". J-frames are very easy to carry in a wide variety of ways, just not as easy to shoot as well as a K or L frame. Of course a model 66 or 686 or something similar with at least a 4-inch barrel will have it's own advantages at the cost of weight. You just have to choose where you're willing to compromise. Personally, I wouldn't want to shoot magnum ammo out of any J-frame. But I wouldn't hesitate to do so if I thought my life depended on it. If you choose a J-frame, though, you'll likely have to practice even more to get (fast and) accurate with it and not flinch with hotter and heavier ammo.