I find a 4" m19 more comfortable than a G19 and even 1911s. Yes it is technically thicker at one spot but it's thinner and rounder so it feels like there is less mass.
I'm looking to pick up a 2.75" m66 and am tempted to cut the holster, or leave it. I don't find it uncomfortable.
As for power? .357 Magnum still has some umph from shorter barrels. The biggest problem is with j frame .357s. the bigger grip of the k frame handles recoil much more effectively.
I'm very comfortable with 158-180 grain hard cast bullets with a wide metplate for bears.
Accuracy? This is my wife's M15 at 25 yards