It is until you push E. Then you’re locked into a cast animation for 1.75 seconds with -75% move speed. That’s not fluid.
It is until you push Q. Then it disappears completely because of the chain beams.
Those 2 things are the biggest complaints about current Mercy. The third would be her very distinct lack of ways to respond when things start abruptly going down hill. All other healers have abilities that let them respond to bad situations. I’m really not sure why Mercy doesn’t have at least one.
Here’s a news flash… fixing these problems does not necessarily require breaking the things you love about Mercy. Maybe… something like this.