Sorry to say I just can't get worked up over this. These are bicycles, not sacred things that can be defiled. If you own it, do whatever makes you happy. Paint it, powdercoat it, leave the rust, put old parts on new frames, new parts on old frames, make sure no two components are from the same era---it don't matter one iota. I have my own preferences about what I like to look at, and what I like to ride, but I never question anybody else's choices.