I don’t know if she’s the most OP merc in the game, but she does have unfair advantages over other medics.
Why can she quickly heal herself to full and tank damage? Sawbonez can’t do that. If the station is around a corner and she’s bobbing in and out then she’s incredibly hard to kill. I shouldn’t have to walk past a merc with a shotgun and her friends to deal with her healing ability. That’s absurd. I shouldn’t have to switch to Fragger either. I don’t have to do that with any other medic.
Why doesn’t damage stop her regeneration? Again, it does with Sawbonez. Aura arguably has a more damaging weapon than Sawbonez, far faster movement speed, and more effective health when near a health station. If I damage a Sawbonez, his regen stops. If I damage an Aura, she just keeps on healing. Why?
Why does the health station have so much health? My friend regularly complains that even sticky bombs aren’t always enough to destroy it. It takes like 4-5 Dreiss shots to destroy. Sparks is easier to kill than a health station. Not to mention that I then have to kill a full health aura after that. She effectively has a taunting, aggro-keeping healing tank pet.
To kill an entrenched aura with a well placed station you need to consistently shoot her in the head and out-DPS her healing. You don’t have to do this with any other merc. Combined with the fastest movement speed and access to the most damaging shotgun and you have an incredibly strong merc that requires far more planning and skill to defeat than other medics.
I’m not saying these things make her the most OP - Fragger is a strong contender for that - nor am I saying these are impossible obstacles to overcome, but these traits do make her stronger than she should be.