Why are the golden cups gone? A golden cup is nicer than a 'V'. And maybe a platinum cup when the lessons are done without losing any hearts?
Louis, they're still there in your public profile that other people see, but just not on your Home page for some reason. I'm sure you know this but for anyone who doesn't, you can see your public profile by clicking on the little person icon in the upper right corner.
P.S. I really like your idea of the platinum cup if you finish all lessons in a skill without losing any hearts. Good idea!