That's a good suggestion and I've given it much consideration and a bit of range time. I took one out to the range to practice pocket carrying with the other day, but the slight size difference made a big difference in a pocket. I do like shooting a G43 and love 9mm, though it's not a good pocket carry gun for me. Even the G42 is a bit of a stretch.
I also tried a P938 to run alongside a G43, which was nicer in the pocket compared to the G43. Both were doable, though I shoot the G42 considerably better than the Sig on drills and can shoot the nose out of a B 60 target in less time, every time. The P938 felt a bit smaller than need be for IWB and if I'm going IWB, I'd likely prefer a Shield or even G26 to the G43.
I'm up in the air a bit, though after carrying J-frames for a couple of decades, I'm much happier with the Glock 42's (for me) speed, accuracy, capacity, reloads and mostly okay with XTPs. I'd rather run a 9mm, but haven't found one I like for a pocket unless I gain some weight and pants pocket sizes. If going primarily IWB, the G42 might not make the cut over the G43 or Shield, but I do see it filling a pocket, ankle, or deeper concealment niche for me.
That said, I'm picking up a new G42 today or tomorrow, but am also going to grab a single stack 9mm this week for IWB in 100 degree plus/shorts, t-shirt, and sandals weather or deeper concealment than my G19s or 1911s. G43 is not entirely off the list, but I presently favor the no-safety 9mm M&P Shield and even G26 a bit more.
I should mention that these carry options are for Northern California, where I'll be moving soon as my wife got a job offer that we just can't turn down, so <10 rounds and need to limit printing as much as possible. Up here I pocket carry a 642 or G42 and/or carry a G19, G20 or 5" 1911 without trouble depending on what I'm doing. In California, my goal involves a deeper level of concealment and, obviously, some compromises. I'd rather fight with a G19 and will still carry it even with 10-round mags given my abilities with it, but the 10-round limit has me for the first time considering single stack 9mm and G26, the later I tried and did not like more than ten years ago, but I've learned to shoot a service caliber semi-auto lot better without a full grip in those years.
Pocket carry, though, has always been more about a BUG or idiot tax for laziness for me. I totally buy Ken Hackathorn's thoughts on conveniently small pistols, but I'm also a lazy bastard sometimes and when I'm lazy, I carry nothing, though I've found a pocket gun is almost never neglected and almost always carried including at home. Started with a 1980s Colt Mustang, then a Chief's Special, then a couple of 642s, but the G42 is a wiz for me, plain and simple, and I really, really enjoy and benefit from training with it in a way I didn't with the revolvers. In my mind it is worth the caliber and slightly awkward shape if it fits better and I can smooth out the draw as much as reasonably possible.
As soon as it's on the waist, though, I agree with you whole-heartedly.