First of all, while a good snubnose in the hands of a good shooter is certainly capable of some surprising long range accuracy, that type of shooting is not what they're designed for. Just about any snubnose will shoot a bit low with lighter bullets; it's a matter of physics determined by the bullet's dwell time in the barrel and motion in the shooter's hand during recoil. But I have never had a snub that shot so low that it would really make much difference in likely self-defense scenarios, or that the phenomenon couldn't be corrected for by simply aiming directly at the point of aim rather than with the "six o'clock" hold that we are typically trained to use. Six o'clock is fine with 158s; dead-on works well with most lighter bullets. And often a standard-velocity light bullet load, as opposed to a +P load, will hit just about dead on even with the six o'clock hold.
Secondly, despite the proliferation of quick-expansion bullets on the market, real-life expansion out of a short-barreled handgun is always something of a crapshoot; maybe it will, maybe it won't. Expansion can be nice, but it can also be a drawback as it almost guarantees less penetration. And even if that .357 bullet expands to .557, if it doesn't penetrate deep enough it's not worth a whole lot. A 158, whether a hollowpoint that fails to expand or even in a SWC configuration, is no slouch when it comes to doing the job. Whatever load you use, the "struck by the Hammer of Thor" effect we all would like to see is pretty much a myth, or at least a matter more of precise placement rather than bullet type.