A 110/2.8 on 6x7 is approximately the same (in FOV and DOF) as a 55/1.4 on 35mm. There's no easy comparison because the aspect ratio differs: when you frame, do you compare the long side, short side or diagonal?
A simpler way is to look at the physical aperture size - that will give you a good idea of how much bokeh there is for similar fields of view. 110/2.8 = 55/1.4 = 39.3mm, and 50/1.4 = 35.7mm.
So many more 35mm systems were made though that good glass for them is easier to find. But if you want large, creamy smooth prints, you need large negatives too.