"Winrate is the biggest indicator of how strong champions are..."
46.3% winrate - crushes malphite, jax, gangplank, and shen given a good enough player, can easily do most damage on team given a dmg build, decides teamfights on even teams
45.9% winrate - Can bully lane/decide teamfights, can single-handedly win teamfights with a good Command:Shockwave, blows up most opposing laners, etc.
(Comment other's you notice! I am just a rumble/orianna main that wanted to share my eperience :D)
can still dominate early, and kick the tank dealing 10k damage to the rest of the team, while being uncatchable due to ward hopping.
46.3% winrate: botlane becomes deadly when he and his support are smart, otherwise he is "garbage". Maybe I should add "learning curve" as a part of that too, since his WR used to be a lot worse.
48.2% winrate: a very team-dependent champ, no matter which lane she goes... I mean, a debuff support can only do so much. Support also has shit WR because of the reason above, and that her support playstyle is so unpopular that you can't tell your typical LoL player to make it effective as a support.