I am also watching this discussion and eating popcorn... :-)
Use of such an FI class role will need a considerable amount of access from other classes to be usable, at least in display mode. This can only possibly be a "bolt on" to other roles with too much access but none-the-less still missing some FI access.
Or MM bolt-on role for the FI folks in emergencies?
It is possible to import objects by class in PFCG, but an FI_ALL role + necessary friends in other classes can only be done via SU24 -> so only via menu based roles with "where-used-lists" and not manual inserts.
Cheers,
Julius