Thanks for the quick response.
Well, the idea is that I would have two levels of membership.
The first level would be for normal users, the second for admins.
So if a normal, registered user wants to become an admin, they would have to fill out an additional form with extra bio fields. After they submit the form, I could either approve it, or deny it. If I approve it, I would change the user type, and by using Formidable Pro, approve the form. At that point the extra fields would be added to the user profile.