I think a base of 50/50 6-row and munich could produce a decent amber ale or American brown (with specialty grains added). IMO, the grainy flavor would pair nicely with the sweetness of the munich for a sweeter beer, and the extra diastatic oomph will keep you from worrying about converting the specialty grains.
I’m thinking of picking up a sack of 6 row. I’m planning on refining my CAP recipe in the coming year so I’ll be going through some.