I'm a fan of the .357 magnum loaded with 125 Grain JHP's or SJHP's myself, but many people find it a "hard" load to shoot well.
If you are considering four legged predators, as well as two-legged, then I would look at the 44 Mag, but for bi-pedal aggressors, and if you can control the round, the .357 magnum is it.
I carry a 3" GP100 and will use a 2 1/4" SP101 as a BUG as soon as I get it back from being "'smithed". The 3rd Gun is a J-Frame "snubbie". I'm a fan/advocate of multi-gun carry, no matter what you're carrying.
The .357 can be had in smaller guns easier than the .44 if that makes any difference. I have and sometimes do carry an N-Frame Revolver, but prefer the l-Frame size as it's a little easier to pack IMHO. The easiest is the J-Frame size, but it comes with increased recoil.
BikerRN