When Kalista ults you it's confusing, small change proposed
The reason is that I lose track of where I am whenever Kalista ults. Especially in team fights when I am focussed on one area, if Kalista ults the screen suddenly shifts and I become discombobulated. I think one thing that can help is if when Kalista ults you, the screen automatically follows you (it centers you but keeps you centered) because as it is you have to aim from where Kalista is and when her position keeps changing it becomes really confusing. Also, maybe make Kalista a different color or glowing (so you instantly know where you are), then make your teammates look greener and enemies redder until ult ends.
Making everything sepia colored isn't really helpful. If Kalista ults I know instantly that it was her ult, maybe tone the sepia down a bit ;)