Ekko is super healthy and balanced, but am I allowed to say something about him?
His Ultimate is a major source of frustration + anti-fun for players.
I am very much aware that as far as Assassins go, Ekko is considered a generalist by the balance team. His damage isn't the greatest, his outplay potential isn't the flashiest but he gets screen time and when he does, people cheer.
And to be honest, I've seen Ekkos in my matches and all of them are healthy. Except for one part of his kit, Chronobreak. The ultimate is what makes everyone frustrated and it never feels rewarding for the other team to see Ekko heal up 50-60% of the damage dealt. And then, Ekko proceeds to dash away and continues to be a nuisance by throwing Q until his other teammates can come to his ad.
On your own team, a lot of Ekko players take uncalculated risk because they think their ultimate will save them, and start team fights even at a disadvantageous point.
When defeating an Ekko who just used his ultimate, it feels like this - "Well, that took awhile." and not "That was an awesome outplay". So, let me make a suggestion to his ultimate
"On cast, Ekko blinks to his hologram and becomes hyperaccelerated (or whichever term you can think of to describe time) for 6 seconds. In this state, Ekko regenerates X% of his health (comparable to Dr Mundo's) and Ekko's abilities strike twice at 60% reduced damage until the effect is over"
This still preserves the healing component of Ekko's ultimate, but instead of gaining a large chunk of health, he regenerates the lost health over a period of time. It ties in with how wounds gradually heal as time rewinds itself, and his damage is changed to strike twice instead of dealing massive damage upon arrival. This gives Ekko much more outplay potential and reduces the frustration that players have with his ultimate.
Tl;dr - proposed change is to reduce Ekko's survivability and give him more outplay potential on the levels of our current standards of healthy assassins.