Mastery Points vs. Grade

So to me it appears that your grade is based on individual skill, but the points are very heavily weighted on winning or losing.

Why?

If I do amazing on a champion, I should get points to reflect that. But as it stands, I only get points for winning the game, like ip. Obviously winning the game is the overall goal, but why would I get less of a reward for doing the same thing, but having a worse team?

In my opinion, the mastery points should be almost directly tied to your grade and performance with the champion, from what I understood this was supposed to give feedback on an individual level, there is no reason to bring my teams shortcomings into it.

As a side note, there need to be some special stats for certain champions in my opinion. It would make it a bit more accurate, anyway. A Nasus should have his stacks worked into his grade, with less emphasis on his score, because a Nasus with many stacks can easily zone enemies and contribute much more on a morality scale, not measured by numbers. And maybe have Singed's poison ticks on enemy champions could be worked in?

One thing I want to make sure, this is heavily affected by role as well as lane, right? Because if I'm a tank and I took and reduced a massive amount of damage, or CCed enemies X amount of times, I want to get equal points to an adc who went 13/3/7.

This is just me throwing some things out since this is only in it's early stages.