It is not so much as to how much power a gun has, as to shot placement. If you can find target wadcutters IMO that is the way to go for carry, and practice.

People stop attacks for two reasons, they cannot continue, or they do not want to continue. Nobody that gets shot, wants to get shot another time no matter how much power the cartridge is. Find what is comfortable to you, and stick to it. If you want more power, consider a personal trainer, or physical therapist to highlight the proper exercises to enhance your grip. Having a strong grip, and good muscle tone in the wrist will make a big difference.

I carry wadcutters in my 38 spl, and 32 H&R, but they are a tad more potent than target. But because the bullet is seated deeper they need less powder to develop pressure. This results in less muzzle flash, which is part of what pushes a gun into your hand.

Welcome to the forum, and kudos to you for taking responsibility for your own safety.