I ran an RMR slide for four years before giving up on it. It never made a difference to my scores when compared to irons at distance and slowed me down mid range, although obviously I am very much a work in progress with pistol shooting. It certainly was not something that bought skill with the trigger, grip, stance, etc.
Clearly you have put in a lot of good work along the way and the RMR now allows you to demonstrate your skills despite your eyesight issues. I believe my scores would be about the same with or without an RMR, but maybe after a few years of dedicated practice I may revisit the red dot handgun.