Mercy is not a difficult hero to play, but she used to be about choices, timing, and decisions.
Before her rework the best Mercy players would decide whether to tempo rez or mass-rez by tracking enemy ultimates, sometimes baiting enemy ultimates, and try to optimize their use of the ultimate based on chance for success. Mercy was easy to play and pick up, but by understanding and reading enemy movements you get really good at doing your job as Mercy.
The rework removed a lot of the decision making and choices. Valkyrie removed the need for target prioritization as chain beams does all the work for you. The choice when to use it is also relatively trivial: use if team is alive and pushing, or if team is alive and defending against push, or if you need to escape and have no GA target. So, you press spacebar and hold a mouse-button, then observe people running around on the ground - not very engaging or fun.
When they removed the cooldown reset on Guardian Angel after successfully rezzing someone it meant Mercy could no longer swoop in and rez, and then swoop out. While this was a minor nerf, it made her less engaging to play and also limited her choices a lot.
When they nerfed rez as an ability and gave it a cast-timer they also removed some of the decision making and target prioritization. It became less about rezzing the right target and more about rezzing a convenient target. Mercy also lost some of her calculated bravery because healing someone in the frontline meant she might end up there alone if her healing target dies and she couldn’t instantly rez this person; so Mercy moved towards the backlines and became less engaging to play.
With the recent healing nerf you have to heal your target for longer to keep them alive, so there will be less swooping back and forth. It makes her a little easier to play, a little less engaging to play, and a lot less fun to play. Swooping around is what makes Mercy really fun, and I think there’ll be a little less of it if you want to play Mercy effectively.
So, I don’t want a revert. I don’t want Mercy to be overpowered. I think if they manage to get some balance between the support heroes it’ll be great. I just wish that after the dust settles and we know how things turn out they start looking at giving Mercy a few more choices and a few more decisions to make to give Mercy players a little bit more room to use their skill… Cause right now Mercy’s skill ceiling is much too low, and that makes her boring.