It’s pretty good. You’re basically pocketing your entire team at once.
I think the problem is you get increased mobility with chain healing which feels counter intuitive. Why get all this extra mobility when you can just heal everyone at once?
I think they should remove the chain healing and double her healing/damage boost with the increased mobility.
This will make it so you have to fly around (increasing the skill cap) and it also feels more powerful because of the 120 hps and 60% damage boost.
It also makes it less annoying to play against since the entire team isn’t being pocketed by mercy.
I think the duration should be reduced to 10 seconds though.