Good Morning, Barry,
To me, the big jump is from 35mm to MF. As Mark notes above, prints using standard paper sizes typically have similar enlargment whether from 4.5 x 6(full frame) or 6 x 6, but 6 x 7 negatives do have a bit of an edge over the smaller formats, especially those from my Fuji 6 x 7 RF with its absolutely terrific lens. Right now, I keep being tempted in the opposite direction from you. The Bronica 4.5 x 6 camera has a definite appeal; someday the GAS syndrome will become too strong, and I will probably yield to it.