Does the new mastery function sound hard enough?

With the new mastery system coming out I can't help but wonder if it's hard enough? I think only time will tell, but if 15 games playing really well is what it takes, and only 30 if you're playing meh, is it really a good representation of "mastery"? I like that it's attainable, but if 20-25 games of just okay play gets you to max level mastery then I'm kinda disappointed because I was expecting level 3 or 4 being something you maybe get on a bunch of champs if you play different stuff consistently, but level 5 being pretty much just one main champ unless you play a ton. My first thought when I heard about mastery being added was this:

https://www.youtube.com/watch?v=IR4s4QswGS4&list=PLF8C97115E5BCBA92&index=43

Because getting to really high levels was such a pain in the ass, it was even a joke about how over focused you had to be. I was kinda hoping for a big challenge to work for, and I'm really hopping when they add more levels to the system it will be harder to get (maybe better rewards even as a result). I'm wondering if I'm in the minority of the community or if people think the higher levels of mastery should be harder to get?