Just to preface this post, it is just an opinion from a veteran GW player.
I'm not even that upset about how much damage she does or her primary homing ability for that matter, what bothers me about Rose is that the entire class is built around taking control away from players and limiting what they can do. This is okay in moderation but that is all rose does, being stuck in a time bubble then being killed before you can defend is not fun. Being turned into a goat and having three abilities that are all joke gestures that get you killed if you use them, is not fun. If you do somehow manage to avoid her abilities by engaging while they're in cooldown, all she has to do is use the scientist's energy warp to escape damage and then KILL YOU from within an invulnerable state, not even the scientist's warp can do that. The entire character is built to annoy and bother, in GW1 we had one stun in game with the Engineer and he only had it to counter the Chomper's burrow ability. Now it feels like everyone has some way to take you out of the fight so you just have to watch yourself die. Shooters are about control, if you can control yourself better than your opponent you can always come out on top. When a game has things like Rose in them, it frustrates people because their lives are no longer in their hands. Cheap deaths are never a good thing in a shooter, that's why Chomper's cheap burrow kills were offset with the sonic grenade. There is no counter to Rose, other than joining the plants team.
I don't think Rose's problem is her buffed state, it stems from a flawed character design and nothing is going to change at this point how annoying she is to fight even if her damage is put back in check. GW has always been my go-to game for relaxation but Rose is the first thing to ever make me genuinely upset while playing GW, even in the beta she was annoying and I felt she was poorly designed. Nothing worse than being ambushed from behind and hit with a slow spell and before you're able to turn around you're already dead, its just not fun. Every class should stand a chance in battle, it should never be that simple for one class to rob you of the ability to defend yourself to that extent.
Sorry to vent but Rose is bad, down to the dirt she grew out of.
Fun to play as, not against.