I pocket carry both the PM9 and a 442 Smith regularly, since the discussion is getting around to revolvers as well.
Both work well in the weight department. How much weight you can tolerate will depend on you, but I like to keep loaded weight to under 20 oz. or thereabouts. If you can handle more weight, then your options open up considerable in both the small revolver and auto choices.
Both are reasonably small and flat. The PM is flatter (naturally). But the 5 shot Smith is flat enough and I think that too much is made of a revolver's cylinder "printing". I really do.
The Smith draws Much easier and quicker due to its design, especially with wood boot grips. The PM, while it does not snag, is not as smooth or as quick as the Smith. It just isn't. Its a blocky auto. A small blocky auto, but blocky nonetheless, compared to a "hammerless" Smith. It's slower and more cumbersome, despite its size.
Like someone else said, there is a "positive feel" when drawing the Smith. As smooth and fast as pocket carry can get.
I would say that the PM draws about as smooth as a Hammered small, light revolver, like the Colt Agent (which I also pocket carry now and then). I find I need to "thumb-over" the hammer of the Agent and the back of the slide of the PM to insure a decent draw.
You really need to try a few different pocket holsters to decide what works. You should perhaps consider starting with a Mika (for both PM and J). I really don't think you need a high-class expertly molded expensive holster for pocket carry as "retention" is not an issue. Just something pretty basic that covers the trigger and allows for a reasonable and safe draw.
In terms of larger caliber autos, you might think about the PM 40. Or maybe a J frame .357 revolver. The PM 45 might be ok, if you dont mind the extra weight and you can wear pants with pockets big enough to make it work .