Solo queue reflecting individual performance (regardless of in-game stats)

I'm sure this has been a subject of discussion many times in the past, so I hope you'll indulge me for just a moment. For the record, I finished s4 in Gold after being demoted from Plat twice for inactivity.

My idea is a supplement to the current MMR/LP system. On top of your usual gain/loss for winning/losing, you'll have the opportunity to "upvote" a teammate that you feel really made a difference and outperformed other players, despite the loss. If you're upvoted frequently, it might function as a sort of buffer for LP loss and help with your overall climb up the ladder. This creates a variable that is capable of monitoring the quality of your performance in a way that is not as black-and-white as winning or losing, and can help create a more accurate and reliable gradation of player rankings in solo queue.

You would be limited to upvoting only one teammate per game, and you would not be able to upvote a duo partner. This also serves as a positive reinforcement against players becoming toxic or raging because of the poor performance of their teammates; instead of giving up or afking, there would still be the hope of being recognized by your teammates as having been a positive factor in the game for your team.

My thoughts:

The current system is based entirely on whether you win or lose a game, and some will argue that your overall performance has a considerable enough impact on that stat. While often true, most of us have probably experienced a game that we couldn't carry despite having positively impacted the game for our team. As such, the environment of solo queue is shifted very heavily in favor of the most skilled players who can single-handedly carry their games, leaving little reward for those who performed better than others, yet still lost.

The players who should be high Diamond+ get there easily by carrying lower-level games, and those who shouldn't be, don't. That's fair enough, but then what exactly is setting apart players below that skill level? Should hard-carrying be the primary quality that sees positive reinforcement in a game that heavily favors team play? For a system that has such a vast range of rankings (27 grades total, from Bronze 5 to Challenger), it's incredibly rigid in its evaluation of skill, and I think this addition might help improve the health of ranked solo queue.

FIn.