Frontendusers works like a kit. You can select extensions you need like first name, last name, company etc.
So there is no restrictions. You can made your own plugins or delete fields you don't need.
Structure of the plugin
Frontendusers plugin contains field folders which extends frontend user, php class to perform CRUD operations and sql file wich creates base reference table.
1.Execute main sql file, after that you will have new table in the db 'con_pl_fe_user_data'
2. Copy all field plugins you need and execute their sql file, this step will extends your existing tabelle with columns you need.
After this step you will see new fields in backend of CONTENIDO under Administration->Frontend new fields