IMO
If her wish and abilities mainly revolve her, than she should only be able to erase things that she has an impact on, memories of people, it should like, only be things that involve her.
E.G. If she was/wasn't really there, What she did/didn't do.
I think erasing a person is a bit much, because they're an entirely different person.
Like I said though, In my opinion, your characters erasing powers should only effect things she has had an impact on or things that she owns. That's how I see the wish. If she wished that she had never existed, her powers should revolve around effecting things that were of her... ahaha. Other than that, I like the character .-.