You have the PPQs and the CZ-75BD (which is one of my CC guns, and conceals rather nicely on me). This was largely how my gun collection started. My next purchase, were I you, would be a good revolver, as others have suggested. I would strongly reccomend a .357 Mag revolver, as this will be a largely HD gun. I own a S&W Model 19, have owned a Ruger Security Six (sold it, kicked myself, and am getting another one) and a Rossi 972. I would steer towards a Ruger, Smith, or Colt at your price range, and you should be just fine.
Once you own your first wheelgun, you'll find that you will always have one around...