Although I had an old bolt action 410 shotgun and a 1911 Steven's 22 caliber pump rifle in my hands at the ripe age of 11 years old, and carried one or the other daily on my family's farm growing up, I'm a reasonable shot, but hardly a weapons expert. Therefore, I find the many expert weapon recommendations here interesting, authoritative, and helpful to me.
But I was always trained to study and put myself in the place of the "enemy" and not me. Therefore, if I were a bad guy 'perp', I doubt if I would be ever concerned about whether you had a Sig, or a Glock, or a 1911, or a PPK. If I'm a bad-actor perp, and you pull something on me, I'm outa there!
The key for you is to fire a number of weapons. Experience them. Find one you are comfortable with. Find one that works. Find one that fits; find one you like, find one that will be your friend in a life-threatening situation. Everyone is different, and everyone has a different, favorite firearm.
For home defense, I like my 12 gauge with 00 buckshot, along with a Ruger GP 100 357 magnum revolver. But you would not likely like either one, nor would others. But I'm happy with them. Therefore, just get what you want, and feel comfortable with.
[My son incredibly shot his first white wing dove with my 410 at age 8. Now, my adult daughter, last week for the first time ever , asked to go to the range to fire my 357 Magnum. I think I need to quickly buy rent or borrow a lower caliber for her to start… but as a father, I am as happy with her burgeoning interest, as I was with my son's dove, 20 years ago.]