My G21 is way too damn big for concealed carry in south Fl. I don't dress like Don Johnson(Crockett), either, so a shoulder rig won't work.
Usually, pocket pistol in .380, or my new .38 snub, IWB. It just hugs the hip, still retains movement, sit comfortably, etc,...
Now that it is "cooler" my M+P .40, or FN9, fits IWB better than my G21, which is a railroad tie wide.(not the sf)...same for my full size 1911. Simply less clothing. I tried smaller Glocks for carry, but they lumped on my side. (just a personal thing).
I voted other, as the question covers alot of ground, especially if climate, is a factor. Snubs and sub compacts of all makes would seem likely.
Unless you have a -10 below North Face, Fargo winter coat, and long johns, hoody, and sweater,etc,....than you could get a T/C Contender under your coat,...maybe even a SERBU...
