What I prefer is a QB is net positive for the patterns, which I believe short QBs are not. I don't want lineman trying to create passing lanes because my qb "cannot see over the line". I want them just to block the guy they are supposed to be blocking, not worrying about blocking a particular angle because we a have smurf at QB.
I believe Young and Montana were both 6-2 (or at least listed at it). You're correct though I would have missed on Brees but he was an exceptionally rare player. Wilson, I recall even during his good years he had to move around for the lanes.
I also think due to offenses now being so horizontal that a bigger QB is needed. I see so many advantages to having the Marino, Kelly, Flacco, Allen's, heck even Lawrence's of the world.