Whenever I carry anything but a Swiss Army Knife, I always need some tool that I'd have had if I'd carried one.
Victorinox is the only remaining true Swiss brand, and for a basic pocket knife, I'd choose the Spartan model. If you'd rather have a Phillips head screwdriver in lieu of the corkscrew, get the Tinker.
I carry a SwissChamp in its fine leather SOS Kit in my briefcase.
I do add a belt knife for heavier needs, usually a Benchmade Model 710 when in public. At home, it's usually a Gerber Applegate-Fairbairn Combat Folder. These are worn on the belt in black Cordura pouches. The medium-sized A-F Covert model will also fit in many pockets, and has a clip, if you want that.
You are correct that the basic knife should go in your pocket.
If you want a lockback for the pocket, I suggest the Benchmade Model 705 or the very light, extremely sharp Fallkniven U-2.
Other than the Victorinoxes, none is cheap, but they excel. I'd sure get a basic Swiss Army model first. If you want a slightly heavier knife with Alox scales, try the former military model. I forget the current name, no longer the Soldier, as it was replaced by a more modern design about 2008. You can add a saw blade by getting the Farmer, but it adds bulk and weight. The Alox handles do not include the tweezers and toothpick of the plastic-handled models.
I once tried many models to see which was the thickest that was still suitable for pocket use. That was the Camper. It's the Spartan plus a saw. Yes, the saw does work! But I usually carry the Spartan. If you don't drink wine, the corkscrew is still useful for such things as untying knots. The smaller screwdriver blade on the can opener will usually turn Phillips screws.