"cheated a little and wore a paper thin nylon windbreaker over my untucked polo."
I do a similar thing daily.
Long Tail Tee-shirts and Guayabera shirt as a cover shirt.
Reason I like Guayabera more than Hawaiian is the two lower front pockets I fill with junk to weight it down so no wind can blow it up, as well as to create two more "lumps/bumps" near the belt line for camouflage.
I'm window shopping for a 3" 1911, possibly a hi-cap, if I find something reliable, but currently carry a Glock 26, morphed into a Glock 17 grip and Glock 19 barrel, but a Glock 26 slide. Sorta custom with the short slide due to that "knock the barrel off" length feeling you mentioned sitting down. ("felt like I was going to snap the barrel off.")