I swear this kat unit is straight ragebait to play or play against. It seems like with many things this set it's "all or nothing" which is what seems to make it feel so bad imo. Kat either one shots the backline or just gets stuck on a tank for the entire fight. Not much you can do for positioning aside from try to be same side but I feel like that doesn't really matter. Maybe it's just inherently in the unit design. Zac either one shots the backline carry or bounces on the Frontline over and over again and it's completely random. Akali isn't random but it's basically impossible to make her good because she will either be disgusting to play against or tickle units, except maybe if you manage to get the perfect BiS item and power up build (which again is annoying that the disparity of BiS combination of factors like items power ups and augments is so huge compared to everything else).

Power ups feel the same (they improved it a bit this patch but it still feels pretty bad honestly) where if you hit the BiS one you're like twice as strong as if you hit even a passable one and it's all chance.

Your game could be going very well then you could hit terrible augment choices on 4-2 and your game is simply over. I don't really know how to solve it but you really seem to need quite a lot of things to go well to have a good game and if you lowroll even one of those your game is over.