Mastery lvl 6-7 system is very stupid...
...but I'vent seen anyone come up with a better idea. Know why? Someone has to consider all those players already having millions of mastery points with certain champions. At what milestone it would be fair to have lvl 6-7? Riot made a big mistake when they didn't release mastery levels 6-7 right away when the whole system was implemented. Now it makes it look like a money-grabbing system. They're dealing with consequences.