On a serious note, we've had this debate endless times.
Grading can only ever be purely cosmetic, as even the user makes a difference as to how the bat performs. When the Stig gets hold of my Butterfly bat, I expect to see it fly in a way that it will never do for me.
Having said that, the SG VS319 that I had, which had ruler straight grains, no blemishes and looked beautiful was, without doubt, a complete dog. No-one who used it liked it. It felt dead. It absolutely qualified as Grade 1 for looks.
As others have said, grading is not and never will be a good way of determining how good a bat is, just how beautiful it is supposed to look, and even that is in the eye of the beholder...!