Personally I don't think you'll gain much by staining black and sanding back on a veneer, and the more you sand, the more there's an increased risk of sand-through. I would have a different opinion if it were a genuine maple cap.

If you want to get an idea of the contrast that will appear naturally, just wipe the top with a rag dampened with metho. It evaporates quickly, but you'll get an idea anyway. Also metho won't raise the grain much and will highlight any glue spots.