The current syntax of GRANT is inconsistent between privileges and roles. Specifically, for privileges there is the `WITH GRANT OPTION`, while for roles there is the `WITH ADMIN OPTION` which has a similar effect (looking at the langref).
I would propose that for roles the `WITH GRANT OPTION` is also added. The `WITH GRANT OPTION` means that the user can 1) grant this role to users and 2) revoke from users the role granted by this user, while `WITH ADMIN OPTION` means that 1) the user can grant privileges to this role and 2) grant this role to users and 3) revoke this role from all users irrespective of the grantee.
For privileges a `WITH ADMIN OPTION` could be added with the same meaning as `WITH GRANT OPTION` for consistency purposes.