Let's be real here: Katarina isn't an assassin anymore.
She just isn't. She can't deal tons of damage in a second or in a fraction of a second.
Most of her damage is put into R and passive and well: a) Nobody is going to let Katarina just ulti them (they either run away, kill her or cc her). b) Nobody is just going to sit around her blades c) Blades take too long to land on the ground and "trigger" + damage is also "slow".
I entered Zhonyas on 50% health as Katarina, enemy ADC was next to me with 400 health and I couldn't finish her, even though I used every ability the second I came out of my zhonya's state. My passive blades just didn't have time to trigger.
She quite literally feels like a ranged poke champion that can jump around pretty fast. She "assassinates" enemies by poking for 3-5 rotations and then hope enemy gets near her, when low.
Seriously, do the following:
- more damage on Q
- faster blade "trigger" and landing times
- if you don't want to add more damage to Q, add some damage amplification to W or something.
PS: Down vote me all you want, you unskilled bronze garbage that hates champion, because one can't play against them.