The only thing that matters when choosing a handgun, for any purpose, is how well it fits your hand. If you can't easily reach the trigger with no stress to your hand, it doesn't fit.
Go to your local gun shop and try a few on for size. If you can shoot it, that's great, but it must feel comfortable in your hand first.
Once you find that pistol, you need to try as many brands of ammo as you can to find the ammo your pistol will both shoot well and cycle the action. Then you must practice with it, regularly, using that ammo.
How a pistol looks or the calibre doesn't matter if you can't shoot it well. Remember that you are 100% responsible for where any bullet you fire, with any firearm, ends up. If you can't hit what you're shooting at, you have no buiness carrying any firearm.