Actually, that's pretty close to the system used for most coins in the Japanese Numismatic Dealers Association annual catalogs. They are listed as "shi ta"*, "naka", and "ue" - literally "down", "middle", and "up", but in the sense of "low", "middle" and "high". Some are described as "mishiyoo", "bihin" and "namihin" - literally "never used", "nice", and "regular"; and a few have the additional designations "gokubihin" and "kanmi" - "very nice" and "special" (proof); but that's still only 4 business strike grades. *The word for down is typed with a space in the middle solely to fool the bad language filter.