We need to do something about feeding and LP...
When your mid laner says he's going to intentionally feed because yasuo was banned, there's not much hope for the game, yet you know he'll lose the same LP as you and not be punished. When your bot lane combines as 2 people for 19 deaths and the other 3 combine for 6, you can't win, but they'll lose the same LP as you.
Now im not saying you should focus on K/D/A or that ranked should, but someone who goes 3/10 clearly shouldn't be playing with people who go 4/4 on that same team against those same enemies. Yes, everyone on the losing team should lose LP, however people who feed extraordinarily NEED to lose more LP than everyone else, not only to expedite their demotions but also to just make the players who TRIED to win feel like it was worth trying. If top goes 9/3 but their bot lane went 2/20 combined and mid was AFK or intentional feeding, at least the top laner can say, "well at least I'll only lose 10 LP and thankfully I won't have to play with that bot lane again if they keep losing 30 LP for feeding like that."
Bottom line is RANKED has to rely on something other than a black and white win/loss where you only have a 20% affect on the outcome of the game, having 4 random teammates.