I am not a bad shot, just not quick on acquisition as I would like.
Some of that can be due to old eyes, and a lens will fix it. The relaxed human eye will focus at infinity. To focus up close, your ciliary muscle flexes to squeeze and reshape the elastic lens. As we get older, the lens loses its elasticity, so it cannot be squeezed as far (hence we cannot read), or as fast or easily, so we can see intermediate distances like the front sight, but it takes us longer to focus, and we can only hold it for a few seconds before it fades. Looking at the front sight also fatigues the eye muscle, so you can do 5 or 6 shots, then it gets more difficult at the end of the shot string.
You can try the aquisition experiment yourself: close your eyes (which makes your eye muscle relax and your focus goes out to infinity), then put your hand in front of your face and open your eyes. You can count in your brain how long it takes your hand to come into focus, and it is a few tenths of a second. Try the same thing with reading glasses on (which artificially shift your relaxed focus closer to you), and when you open your eyes, your hand is in focus instantly.
So adding a shooting lens that focuses your eye at the correct distance for shooting, and when you bring up the gun, your focus is instantly perfect.