This.
It would also prevent us from seeing when a player is beginning to regress. When the ratings start slipping one knows to move in a different direction immediately. It will force us to pay attention to stats more and observation while playing.
You could also incorporate scouts into this and have better front offices seeing a more real time asesssment of color or grade changes.Where poor front offices maybe see it at seasons end or end of training camp.
Right now If I have the Vikes I can see exactly when Bridgewater becomes better than Matt Cassel and make the switch. All subjectivity is gone.
And as others have said you change nothing about how the ratings function. You are just hiding them and showing a generic color in it's place