@riot: i think youre going the wrong way about it with the mastery levels 6 and 7
youre trying to come up with some convoluted system (that franky doesnt even have much to do with the mastery of the chamion youre trying to get to lvl 6 and 7 anymore), to make it hard for people to achieve these new mastery levels.
my guess is youre seing the same problem with it as i do. in a couple of month after you added the new levels, people will have their champions at mastery 6 and 7 and will ask you to give them more levels.
so why arent you instead making the system open ended instead of giving it some sort of cap? there are a couple of ways to go about it. those are probably just two:
a) make mastery level 5 the maximum, and have the emote display the mastery points for the champion as a number when played. someone who has a lot of mastery points in a champion could show this off by flashing something like "600k" on top of his mastery emote, which would be pretty statisfying.
b) similar idea. remove the level cap entirely, have 1 emote for mastery level 5 and above and have the current mastery level displayed on top of the emote as a number. so flashing a mastery 5 emote would display somethign like "lvl 20" on top of it.
now that you made the resources for it, just add the mastery lvl 6 and lvl 7 emotes. maybe even go up to lvl 10 with new emotes every level. and from there on have the mastery open ended like described.