You should try a "Surface Finish - Steep" op on those faces to clean them up after you've roughed out most of the material. They appear to be more or less exactly what that routine was designed for. You should end up with long tool paths going up and down the steep face to knock down the ridges left from the z level roughing.
Or, I suppose you could use a Surface Finish - Scallop routine and define the maximum scallop height you'll accept, though I would think that would end up creating many more tool paths than the Steep routine. But it's another tactic to look at.
That's the nice thing about Mastercam, there are about 40 different ways to do any given part.
Ryan Shanks - Logic Industries LLC
http://www.logic-industries.com