I'm about to try to match a new build as well, and just had a thought. Would differing rake/trail geometries wind up creating subtly different fit requirements?

I mean, if the handling or shock-absorbing characteristics of a frame are different, or handlebar shape/width, crank length, or even the Q factor in the new cranks... would your dialed in fit on bike "a" be so surely ideal on bike "b?" Just a thought experiment.