When I go to work, store, errands, ....
I have a 1911 IWB with at least one spare mag and a Glock 43 in my weak hand front pocket.
I don't want to bet my life on anything less than 9mm, so the 2nd option gun in pocket is 9mm, if I needed a bit smaller package my Kahr PM9 would be it.
Perspective: I've been carrying concealed about 25 years.
I work where casual attire is okay, so I have options for carry.
If I worked in a "non-permissive" environment and had to tuck in my shirt and wear dress pants (been there before, it sucks) pocket PM9 would be my first choice, if that would not work, them I would pocket carry a LCP 380 but not be content with its ASAP stopping potential, could also wear a Smartcarry with something in a decent caliber.
Some people carry 380 (or smaller) when they could carry something bigger, I aint one of them.
Like the OP, I see merit in a 2nd option gun.
-Can put my hand on it without revealing I'm carrying, comforting if approached by someone "shady" in parking lot, for example.
-If something happened to dominant hand (use your imagination) I can draw pistol with weak hand.
-I had an extractor edge break on Glock during practice causing demonic jam, not quick to clear and gun had broke part (revolver could break part, firing pin for ex).
-I had a squib "premium" factory SD load lodge in barrel (could happen with revolver) gun was disabled until I could pound bullet from barrel.