presspass
filmshooter
Another vote for the 35/75 combo for the M8. My favorites are a pre-asph 35 Summilux and the later 75 Summilux. Wonderful lenses that seem to work well with the M8. If I add a third, its a 21, usually a 28 pre-asph Elmarit.
The 28mm Summicron is a natural fit with the M8. It has a near-universal balance of sharpness and contrast in combination with the camera's sensor. The crop factor makes it a more useful lens for me than it would be on a full-frame body.
The crop factor makes the choice of just one second lens a bit of a challenge for me. It's a toss-up between the 35mm Summicron ASPH and the 50mm Summilux ASPH, although both of them have higher contrast than the 28. If I had to choose, I would go with the 50.
I agree with your comments on the 28 Summicron asph on an M8/M8.2. In fact, it's one reason I'm reluctant to move to an M9.
Jeff