I don't think she's a major problem right now, but I also don't think champions like
or
should be a thing.
They'll leave lane 0/5, and then get a triple kill out of nowhere.
It's not that I don't think you should be able to comeback from a bad lane as an assassin type champion, but you certainly shouldn't be a high level threat after you fed and messed up.
I always have to treat a 0/5 Kat like she's 5/0. What I will say about Kat is that at least she is team dependent, so that makes up for it. She does require someone who is willing to engage, otherwise she gets locked down really quickly and that damage goes to waste.