The AR platform is easy to shoot well. That's the whole point of the design really. No recoil, light, easy handling and accurate. For self defense, I'm not really sure what a red dot adds, but then, as noted above, I don't have any experience with them. Put it this way, at the range I would anticipate a self defense encounter occurring, I am not missing shooting from the hip. If you are shooting at someone 100 yards away, you are going to have a hard time convincing the cops it was self defense, unless maybe one of the cartels is after you.
I have a decoration for expert marksmanship with the M-16. But that was 40 years ago and my best shooting was prone position. Not exactly workable with a 30 in it. My buddy will straighten me out I think. Resting the weapon on something like a fence or tree branch and shooting from some upright position.