Riot's new creations have a tendency to flip the game on its head, due to their overloaded kits and overpowered mechanics. Renata, though, seems to be on the tamer side of this.
Once Renata Glasc's abilities have been revealed by Riot Games, the entire community stood up in arms due to the, seemingly, overpowered nature of her kit. It matters not if Renata is ahead in the game, or behind, the utility her kit provides ensures that she is dangerous in any case, at least in theory.
After all, one of her basic abilities is a pumped-up version of the Chemtech Drake Soul, which had to be removed from the game entirely due to its destruction of balance in the game.
Renata, on the other hand, has proven herself to be on the tamer side of League of Legends balance. Even accounting for the fact that her win rate is lower due to players just picking her up, Renata Glasc's win rate is still below 50 percent.
This lies in the fact that players have learned to play around her abilities ages ago, just on different champions. Her Bailout needs to be waited out like Sion's passive or Zielan's ultimate, while her Ultimate ability has to be countered in the same way Seraphine's, Brand's, or Malphite's does, by keeping your distance and not clumping up in fights, and her Q is a discount version of any hook in the game.
Had Renata been released earlier in League of Legends history, players would have a much harder time adapting to playing around her kit. As it stands, Renata has the potential to win games for her team, and be incredibly annoying to the enemy. But, this is nothing new, as we've had champions like Lulu in the game for years now.