I'd take good eyesight over custom fitting any day of the week.
When I was a young'un I could shoot at and hit just about anything within reach of the gun, and it didn't matter what the gun's dimensions were. I am one of the humans who was born with arms that bend at both the elbow and shoulder and a neck that can move a few degrees. That always did, and still does, take care of the gun fit issues. What I don't have now are eyes that can put it all together.
Boy, you said a mouthful there. I wholeheartedly agree, and my experiences have mirrored yours. One exception for me is that I absolutely cannot shoot a shotgun well that doesn't have enough drop. I will not tolerate a gun that I have to cheek too hard to make it shoot flat. Fortunately, with vintage guns, that is seldom the case.
SRH
