What if a "grading" company....?
 

Instead of a # grade on the flip.....supplied real world stats like:

1) Size L-R
2) Size T-B
3) Squareness
4) Color gradient
5) Centering % L-R
6) Centering % T-B

Is this, or has this, ever been offered?

Too complicated
 

most people need it more simple which is what the grading companies offer. I do like the Beckett subgrades which I think is in the direction of what you suggest.

Measuring centering digitally is not a difficult concept, and would not take a ton of work IMO for grading companies to implement. They won't do it though, citing time spent on each card that would further delay turnaround times.

I would be in favor of something like the following:

Pay a little extra for an explanation of the grade given or what kept a card from reaching a certain grade.

It would be really nice for a card graded Authentic or Altered to come with an explanation. Several times I have asked sellers why the card is graded that way, and usually the answer is that they have no idea.

The real answer is, nobody would care. Same business would flow to the big 3 despite how incompetent they are.