I carried Glock on duty, off duty, and every day since I retired. The reality is, though, that if I had to narrow it down to one and only one to do everything....I'd carry my Glock 20 in 10mm. You can get the "10mm" lite which is a 180 gr JHP at just a little over 40 S&W velocities and ballistic efficiency ~or~ you can go with the full power 180 to 200 gr JHP or JSP loads at 1300 to 1400 FPS for a 41 Magnum ballistic equivalency.
Lately, and for about a year....my every day carry pistol has transitioned to the Glock 48 with a pair of 15 round Shield magazines. It's more size efficient than my beloved Glock 19s, yet carries the same number of rounds.
BUT....it's a good thing we aren't limited to just one gun. I'd be bored.