The S rating system is so utterly unreliable that it's not even funny.

In one week, I've got no less than 11 A+ and 0 S. Do you know how that feels? Horrible. Just in my last game, I did substantially better than a Xin Zhao as Ashe in just about every aspect except damage taken and somehow he got an S and I got an A+. By now, the key drop rate actually seems way more reliable to me than the S and A+ criteria. Meanwhile, I'm basically forced to play champions that I haven't previously got S with so that I can actually maintain a chest income. Are there any plans to further define and balance the rating system?

From the top of my head, if you look at my match history, I got an A+ in: The 12/6 Ashe game The 16/11 Vlad game The 3/6/11 Mundo game The 8/5 Sivir game The 11/4 Ashe game

That's all I can remember for now.

EDIT: I KNOW that these aren't great KDAs. For one, you guys need to check my match history for these games. Everyone knows that KDA is not everything, stats like champion damage, cs, and towers destroyed are important too. Nonetheless, it doesn't at all matter if these are bad scores if there are people like the Xin Zhao from last game getting an S (not an S-, an S) when he went 12/11/10 (I went 12/6/12) with less damage and less cs than me. I know that I've gotten S ranks from scores even worse than these too. The point I'm trying to make is that the rating system makes no sense at all.