For me, 4" barreled revolvers are best balanced.
For self-defense, again I'll go with a 4" barreled revolver, that's, of course, assuming I'd be going with a revolver in the first place. Quickness to battery is essential when a bad guy(s) want to reduce you to room temperature.
Under 4", I'd go with a 158 grain lead SWCHP .38 Special +P over any .357 Mag every time. The .357 Mag loses too much velocity in barrels shorter than 4", recoil causes sight picture retention to become difficult, and muzzle blast is disorienting. BTW, even with a 4" barreled .357 Mag, for bipedal self-defense, I'd almost certainly go with a 158 grain lead SWCHP .38 Special +P.
I used to own a 4" 586. I could conceal a VW better than I could conceal it.
I've recently bought a 4" GP-100. No buyer's remorse with that one. I had given thought to actually carrying it. For some reason, last night I reflected upon years of training and knowledge. The reality is, the 1911A1 chambered in .45 ACP is still at the pinnacle of the self-defense handgun pyramid. However, I am partial to my Sig P-229 in .40 S&W with 13 rounds of 180 grain LE ammo.
As much as I like my GP-100, after careful thought, revolvers cannot compete with large caliber, good quality semiauto pistols for bipedal self-defense. There's a reason why no law enforcement agency of which I'm aware even allows revolvers for on-duty use. Now were we to limit self-defense to black bears and mountain lions, six 180 grain .357 Mag Partitions would be tough to beat.
I think I'm going back to practicing a lot more with my P-229.