Originally Posted by Windscale
yes and no.
Yes: Bigger film size for larger blow-ups.
No: I found the lenses of the Mamiya too sharp and contrasty and lacking in shadow details. Not quite the creamy German feel even with lower contrast films such as the Fuji 160S or Kodak 160NC.
I would, however, do a swap for a Rolleiflex TLR 75/3.5 Planar, Xenotar or even Tessar. But they do mainly standard lenses. You can, of course, get wide and tele lenses too.
Lack of shadow detail is an exposure problem, not a lens issue. Give your film more exposure.