Champion mastery rewards

What about adding summoner icon of a champion for really high champion mastery level? (like 200k points). The icon would be a little bit different from default champion icon, there could also be 3 different icons for one champion, unlocked for some mastery levels (like 100k - mastery lvl VI, 150k - mastery lvl VII, 200k - mastery lvl VIII) But the icons wouldnt be same with just chaged color, but 3 different face expressions etc... I want icon of raging without mask :P

Giving skins for champion after reaching some mastery lvl is not good idea, mastery lvl rewards should be original and champion mastery should be the only way. Having 200 games with champion might prove you are good with that champion a little bit, but just buying a skin won't prove anything.