She now has the highest CD ultimate on a mid lane champion (not including globals). Normally the max is 120 seconds, but it's +15 for Kat because of her passive.
I can see the reasoning behind this. Katarina's level 6 is probably the best in the game - EWQR and they are dead; no skill required. If she gets a lead early on she can push that lead further because her 90 second ultimate will be up before the enemy's. But to increase it by a disgusting 50%? That not only makes it the longest non-global mid ult CD in the game, but also guts her early game substantially. Now if she doesn't get a kill, she's boned for 135 seconds, and Katarina scales terribly. She can't even build CDR effectively in her items because nothing with CDR gives enough damage for her.
So instead of this incredibly mundane and lazy change, I propose you guys change how her ultimate works. Right now it's literally press R to win. The damage is absolutely fucking insane. You can legit E->R someone and if they don't leave they will die unless they are tanky.
I propose gating her ultimate similarly to how Yasuo's ultimate is gated by knock-ups. Her ultimate's power should increase based on the number of daggers she has picked up in the last X seconds. If she has 0 daggers picked up, then it should only do like 200 dmg over 3 seconds rank 1 and only target 1 person. If she has more than it does more, channel time reduced, targets more people, etc. eventually reaching her old ultimate potential or going past it. This makes her much less frustrating to play against, and less braindead to play as, since EWQR would be far less effective if she has no dagger stacks. A FAR better change than simply nerfing her early game ult.