Polymer-framed 9mm is the best bet. Size, capacity, grip angle, and red dot or fixed irons are your main options. All modern pistols are damn good today. If concealed carry isn't one of the roles, go full-size. They're better in every way except carrying.
Don't fall into the 10mm (or .45 or .40) trap. You won't use it on a charging grizzly. Get a 9mm, shoot it often, and know that you likely won't ever have to use it, either. But if you do, it'll be second nature.
Find the pistol that fits you best. That might be Glock, could be S&W, or maybe it's Walther or Shadow Systems or 200 other options. My choice for what you describe is a Glock 48 M.O.S. with a Holosun EPS Carry. It's thin, reliable, and large enough to shoot well. Lastly, I don't want to carry more than 10 rounds, so the capacity is no issue.
Good luck!