Either will work. But they are fundamentally different firearms.
357 is fired from a revolver, so long heavy trigger pull is the norm, unless if cock the hammer, in which case it will have an easier to pull trigger similar to the 1911 (haven't used one, so I can't comment as to how easy). No safety on the revolver. May fire pipsqueek rounds, such as 148grn wadcutters, and up to whatever the frame (or your hand) is rated for. Reloading the cylinder is easy and/or time consuming: easy to drop rounds in, and eject out (unless if it's a snub with a short ejector rod), but longer than a magazine. Easy to reload ammunition for, as the brass can be dumped from the gun into a bucket (no digging around in the grass).
357Mag can have brutal recoil in a lightweight firearm, but so can 45acp. The boom of the 357 can be very loud, even in long barrels. A revolver has the gap between barrel and cylinder, and you have to be careful to keep fingers from that area, due to the expulsion of hot gasses. A revolver does not have to deal with a stiff slide that has to be racked in order to chamber a round.
The 1911 is single action, at least classically (probably some double action out there). I do believe 1911's are easier to take down for cleaning than a revolver, but I haven't taken one apart. Lots of accessories, so you can modify to suit your tastes. But it will be more sensitive to ammunition power levels, due to the need to cycle the action. And you do have to keep your hands clear of the slide, lest you get slide bite. A classic 1911 is carried "locked and cocked" (or at least by some), and that brings into play the safety that needs to be used, along with a higher need for a holster that covers the trigger (not that the revolver doesn't need that, it just needs it, err, slightly less).
Some 1911's can have feeding issues, due to the feed ramp; I'd think that was mostly solved by now. Magazines can also come into play, if the mag isn't right, it won't operate. Revolvers can and do fail, if crud gets under the ejector it won't rotate, or if a bullet fails to leave the cylinder it can lock, just as if the bullet from other chambers pull out under recoil.
45acp is a larger round, so it makes bigger holes, and it can be a bit less loud on the blast. Magazine capacity is also usually higher than the typical 5-6 rounds of 357Mag (686's can go up to 8?).
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Revolvers IMO are cool, but I'm not sure if they have less parts. Maybe moving parts, but I think they tend to have non-moving parts that are just as critical. Feed ramps on the barrel and magazine lips come to mind. But otherwise, yeah, my gut feeling is that they are simpler, and, while harder to shoot they are hardly a bad decision for CCW/home protection. Much harder to have a negligent discharge, due to the heavy trigger.
In terms of a range toy, hmmm, if you ask me a revolver is more of a range toy. When you can shoot a revolver well, odds are you can shoot an automatic well too, as it takes a decent amount of discipline to pull that long heavy trigger properly. Just my opinion.
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I have the SP101, and I don't care for shooting magnums in it. The recoil isn't bad, but the noise is. I much prefer 38spl +P in it. The GP100, I have not shot but it struck me as a very large gun. Much better for shooting magnums from, but at the size of it I'd rather have a rifle. Or a higher capacity automatic.
The LCR, in 357Mag, is a decent carry gun; a bit heavy but that helps with recoil. The trigger is much better than the SP101; on my SP101 I put in a slightly softer hammer spring and while the two triggers are now more similar the LCR is just a nicer gun. On the trigger, that is--the recoil is markedly more.
But the LCR drops into a pocket (with a pocket holster, of course) while the SP101 is too heavy and large for that. Neither strike me as much of a range gun--no long range shooting for me on either of them.
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Both calibers have a long history, and are easy to reload ammunition for. And have widespread availability. Well, outside of times of hoarding, that is. I'm not sure you can go wrong with either, as about half of America owns one or the other, and the other half owns both.
