Not loosing LP based on how you play
I think it is very frustrating to be carrying my own weight in games while the rest of my team, or just a select few, performs badly. Of course, this is not always the reason for losses in ranked games, but they are often enough that they are noticeable. I think it would be great if you got an A- or higher in the game, you don't lose any LP. You might even be able to gain some if you earned an S- or higher. Instead of punishing the whole team for a few bad players, this would ensure that as long as you consistently play at a good enough level, you can always improve. Furthermore, one loss in a ranked game is around equivalent to the gains you made in two wins, which makes it extremely hard to rank up. Of course, you could always grind to get better, but it just makes it so much more difficult and unrealistic.