Of the guns you list that you own, the Rock Island 1911 is about the most concealable. I love the sub-compact 9s, but you can do a lot worse than a snubby .38. I have a Taurus M85UL that is SA/DA. I really like the Smith 642 (don't own one), affordable, and a great pocket revolver with concealed hammer, but you specify DA/SA capability. My little Taurus is 15 ounces, +P rated, a tough little gun with an awesome trigger and I can't beat the price I paid for it, under $300 out the door. It's an excellent, accurate, light, concealable little package in a service caliber.
You can't go wrong with a snub .38, regardless. You won't find any sub-compact 9s that are SA. The Glock comes close, 4 lb trigger with some creep. It's neither DA or SA. There are old Mustang Pocket Light Colts out there used, not cheap. .380 caliber doesn't impress me all that much, but the guns are very compact. In 1911s, I reckon my personal preference would run along the lightweight commander lines. The full size 1911 is so flat and thin it doesn't bulge, it just is too danged heavy. A lightweight commander takes some of the pork off it and in a good IWB, is very concealable. I gave up 1911s for lint, but they are still viable carry guns, just I prefer DA.