Robusto,
I completely see your point about the Python. Yes it's up to the task but a shorter barrel on a gun that doesn't have so much collector or sentimental value would be a very smart investment.
In a 4" .357 Revolver there's basically two frame sizes for most intents and purposes, such as yours. The terms come from Smith and Wesson's nomenclature but other companies basically adhere to this sizing convention because there's only so many ways to build a double action revolver.
The first is the K frame. Here's an article with examples of classic .357 Magnum revolvers in this size, as well as the history of how the K frame and the .357 cartridge came to be:
http://www.gunblast.com/RKCampbell_SWsBest.htm
The K frame is something a lot of people like very much because it's slim, trim, and has a wonderful heft and balance. For personal carry it's pretty nice.
The downside is that the K frame sized guns generally aren't quite as sturdy as the next frame size, the L frame.
Now speaking of the L frame, it was the next size to come along. The problem with the K frame Smith and Wesson revolvers is that a steady diet of even modestly powerful .357 loads tends to strain the gun just enough to make things come loose, causing a variety of problems. Now there's some K frame sized guns out there which are excellent revolvers that will give a lifetime or more of service, but as with anything there's a trade off.
Another issue is that the K frame has fallen out of favor due to these issues, which is unfortunate because like most revolver shooters I like the K frame and I think it has a place. There aren't very many K frame sized guns being made right now, which has made classic K frames like the S&W Model 19 and 66 become very valuable as used guns if they're in fine shape. A less expensive alternative is the Ruger "Six" series (Speed Six, Service Six, etc.) which is analogous to a S&W K frame, size wise, but once again only available used.
The L frame fixes the K frame "problem" by being larger, stronger, and more massive. Basically you'll never wear it out. The upside to this is that your gun requires less tender loving care, the downside is that an L frame sized gun is a lot more gun to carry.
The contemporary benchmarks for what makes a very good and functional 4" .357 wheelgun in the L frame size are the Smith and Wesson 686, and the Ruger GP100. These are both in current production and there's plenty of used and new examples to be had. To be honest as much as I like the K frame, the L frame is the one I prefer both for its balance/feel and its performance. This is subjective however as many people feel the opposite, but I prefer the heavier, beefier L frame because I feel it's more durable and easier to shoot. For a woods gun I think it's ideal. The K frame is easier to carry concealed though (I sometimes CCW a 3" GP100 however so the L frame is certainly not too big).
The model 686 by comparison to the GP100 usually has a significantly better trigger out of the box. The GP100 boasts being structurally stronger due to its design. I also think it's easier to maintain and clean due to the way the trigger group lifts out of the Ruger so easily vs. the S&W, but I also think that's a minor point.
The model 686 has been through several variations (the first being the model 686, then the model 686-1, then 686-2, etc.) and at some point, the company made changes some people don't like. Any new model 686 made today has an MIM trigger and hammer, as well as an internal lock system.
I don't like these features because I feel while the MIM parts are strong and durable, they are aesthetically displeasing on what's supposed to be a nice classic handgun. And like many, I don't see the point of the internal locking system and would rather not have it at all. However if you're worried about utility and aren't biased like I am about these things, you probably don't care about that kind of stuff and you'd be very happy with a 686.
Ideally I'd try to find a 686 with the forged hammer and trigger and no lock, but they're getting harder to find. I'd probably wind up buying a new one and being happy with it if I just had to have a Smith and Wesson.
However in new production guns I prefer the Ruger GP100. As I mentioned before the S&W typically has a better out of the box trigger, but the Rugers can be broken in and/or tweaked to have a very nice trigger pull. My personal GP100 was a little rough and stiff when I got it, but now has a perfectly serviceable trigger and all I've done is fire and dryfire a lot.
The Ruger has forged parts, a stronger frame, and no internal lock feature. I believe if you're buying a brand new gun it's the best general purpose 4" .357 magnum in current production.
But both the 686 and the GP100 are very, very good and ideally we'd all have both. I prefer the Ruger but I can see why someone would disagree with me and prefer the Smith.
The K frame sized guns are very good too, but as I said, a little harder to find new or "like new" ones, and currently the L frame is the way guns like this come. I personally think for your described purposes you'd like an L frame better and should look into the GP100 or S&W 686.
