From my experience of having her played in my games she seems to have a VERY rough laning phase and becomes viable late-game, I have yet to play a game where she has done even remotely well on both my team and the enemy team. Her average KDA in the games I've played with her in it is around 0/7/3 or something relatively close to that. I know that a lot of people are complaining about her being to strong because of her kit but she actually seems underwhelming if played at a relatively normal level. If she is played correctly I would expect her to preform just as well as any other support played correctly and in some cases (thresh, Pyke, and some other candidates for overtuned sups...) worse than if the other supports were played just as well. Tell me what you think about this in the comments, I'd love to read what you guys think!
**Update: this seems to be a very split topic based on the comments and up vote to down vote comparison, very interesting!**