Steve Elliott
". . . how do I differentiate the sub-par from the sublime?"

On woods that take on a "deep" appearance when cleanly cut, the difference in surfaces is dramatic. The deep appearance is due to a property called chatoyance, which comes from the French word for "cat's eye." It's almost like a wiggle picture, where the angle of view changes what you see. In curly wood it can seem like you're looking down into the surface by 1/4" or more. On some woods (African mahogany comes to mind) color matching is not possible because each piece changes from dark to light when viewed from different angles.

Lower planing angles help bring out chatoyance because they cause less distortion of the wood below the cut line. The higher the planing angle, the more force the blade exerts on the wood. This can cause either loss of chatoyance or just a cloudy surface, something I've seen especially on Douglas fir.