Champion Mastery

I feel like the current champion mastery does not reward you based on how well YOU do enough. I get that League of Legends is a team based game, but this is champion mastery. The mastery points you earn each game are the same for your entire team regardless if you go 13/2/11 with an S rank or 1/9/5 with a D rank. If you are both on the same team, you both get the same points. Also, why do points seem to be so dependent on game length and winning? I've won my lane going 5/1/4 and my team surrenders at 20, the points I got that game were less than 150 while the enemy most likely got 900+. I guess what I'm trying to say is that champion mastery needs to be rounded out more to award those who are actually playing their champion well regardless of game length and outcome. The entire team should also not get the same points, that makes my S ranks feel like a waste of time.