i have carried j-frames, pocket semis, ultra-compact semis, compact semis, medium semis, full sized semis, all in steel and poly. i have carried striker fire, squeeze cocking, SA/DA, SAO, and DAO. i have carried in leather, nylon, and kydex. i have carried on my hip, in the small of my back, and in my pocket.
overall, i have settled on ultra-compact to medium sized semis with polymer frames and striker fire triggers in thin kydex holsters carried iwb on my hip.
ultra-compact to me is something in the size range of a walther pps, sprinfield xds, or kahr cw9. it is single stack and just large enough to fit all fingers on the grip. the smaller it is, especially in width, the more comfortable it is to carry. i like rounded edges so it doesn't dig into my love handles. compact is something like an hk p7 or springfield xd sc. medium is something like a glock 19 or walther ppq.
i choose polymer striker fire, because they are the lightest and easiest to operate. you pull the trigger and it goes bang. no safeties to worry about. the simpler the better in a self defense situation when your adrenaline is high. we are not highly trained gunfighters. we are civilians trying to defend ourselves.
kydex offers 2 advantages. first it is thinner than leather, so it is more comfortable and easier to conceal. second, it is a rigid shape, so it stays open for easy reholstering and protects the trigger.
i like the hip for smaller guns because this allows for easy access and minimal printing. as your rotate to 4 and 5 o'clock, the handle tends to print. if you can comfortably access all the way to the small of your back, this is a good place to conceal, but if you suffer from plumber crack like me, you will telegraph the presence of your weapon every time you bend over. the gun will jut out straight back.
Favorite range gun for the money - CZ 75B or STI Spartan V 9mm
Go-to carry setup - Walther PPS or PPQ in FIST kydex holster 1AK
Favorite semi-auto design - HK P7
"A Sig is like a lightsaber - not as clumsy or random as a Glock."