Despite my reality as a lifelong "revolver guy," I more often carry an auto pistol. Not because I feel under gunned, or short on round count, but simply because it's easier to conceal my pistols, and easier to conceal rapid-ready reloads. I most often carry a single stack small frame or micro frame pistol, so I really have no more rounds available in a semi-auto pistol than I do in my revolvers.
I don't carry a handgun because I expect to need to use it. I carry a handgun in case I unexpectedly found myself needing to use it. In those varied circumstances, there is no one answer which exactly suits, without excess in any other circumstance.