In an old interview with Maitani-san himself that I read somewhere, any of the F2.0 Zuiko lenses are particularly good. He used to use them himself FWIW. I have the 35mm F2.0 and 85mm F2.0 and I can agree that they are very good indeed. Especially the 35mm - which one can find quite easily and at reasonable prices as well. Not so with the wider ones.
+1, 85mm F2.0 is one of the gem. Some said, 35mm F2.0 exhibit 'Swirl-Effekt'.
OM-1n: Do I need to own a Leica?
Rolleicord Va: Humble.
Agfa Isolette III: Amazingly simple, yet it produces outstanding negatives.