Heavy-for-caliber. Flat-nosed and non-expanding for anything .380 or smaller. Got to feed and function. Within those considerations, I'm largely indifferent - top-shelf hollowpoints, flat nosed FMJ's, big meplat cast bullets, unjacketed lead SWC's and HP's, even Hickock's .36 round ball was no slouch. . .I'll avoid hard, round noses if I have a choice, but beyond that, load it up.
It's all lead and copper. It's all generally guided by SAAMI pressure specs. It's all governed by the laws of physics much more than marketing. Everybody has access to what the FBI says a combat pistol round needs to do - be shot accurately, penetrate to hit important stuff, and maybe, once it does that, we'll take some expansion too. I'm more worried about a bullet not penetrating enough than too much - misses kill more bystanders than pass-throughs.