The class/role that REALLY needs an overhaul is...
...supports. Supports need a drastic overhaul, and here's the reason why. No one wants to play support!
Team Builder came along, and the only reason to play support was to buck the queue times. Dynamic Queue took its place, and didn't do anything to solve that problem. Now you have players who were assigned a support role trying to trade and/or force people out of their assigned position. Or, when they don't get out of it, they grieve the ADC so that they can carry from the support position. Sure, you can report these people, but that's really a band-aid. It doesn't address the real problem which is... NO ONE WANTS TO PLAY SUPPORT!
Supports need an overhaul so that they can be fun to play. Hopefully, the Taric rework is a step in the right direction. Also, the mastery that allowed supports to gain bonus exp needs to come back. Handicapping them makes the situation that much more worse.
If anyone who mains support has some suggestions on how to make this happen, I'm all ears. We need to make people WANT to play this role. It'll make the game more fun and there will be less toxicity in the bot lane.