Can we please be rated on some performance curve?
It's been suggested before with the common retort being that it would encourage selfishness, and that games can be won a variety of ways. But why? Everyone agrees you don't just go on massive kill streaks to win every game, but we also agree, for example, the tank should take as much damage as possible and keep lots of people CC'd as long as possible. There are definitively positive moves that help you win no matter what the game is. Don't tell me a ward revealing a fairly large chunk of fog and a couple champs isn't helpful, because we all know it is. We can all imagine situations where doing damage to towers does more harm than good, but we struggle to imagine how daisy chaining the ADC with stuns in a team fight would.
We already grade people's performance in games. And with the new Ranked queue coming in soon, it'll be easier than ever before to tell whether that's AP Nunu being beaten to death or Tank Nunu. If Tank Nunu is doing his job brilliantly (By taking damage, CC, slowing people, etc.) why should he suffer full LP losses because Fiora decided to 1v1 Mundo the fifth time in a row? We all agree you shouldn't be able to gain LP after losing games, but can't we also agree you shouldn't lose the full amount when, as far as the grading system would be concerned, you're performing above your team's average?