As if that would change anything. It would be a girl identical to her, but not herself. The consciousness of another individual. Like when I die and get cloned and that guy has perfect memories of mine, I will still stay dead. So in the end it would still be the same sag thing. Except we are talking about a case in which she would not be an actual clone but the same kind of entity Sephiroth is, who can form himself a new body and actually transfer himself, his individual consciousness which is the essence of us or depending on definition, the soul/self (what M. Bison in Street Fighter and the Emperor in the non-canonical Star Wars story can do as well, they clone themselves bodies but don't even give those clones a chance because the body is actually just meant as host for the original) into that body to animate it with himself instead of a cloned person living the life that you no longer have.
So, yeah, I would not want them to do that. It would not change a thing except doing the last mentioned thing. And that also would not be good. Aerith is alive. Just not physically.