The problem is, most of the privileges shown in users-admin are old-school Unix groups that aren't used at all by PolicyKit. So we'd have to support a completely knew privileges tab, based on PolicyKit. Not sure that will happen in users-admin.
Note that an easier solution would be to add an option to allow all users to install trusted packages, that would go in one of the configuration tools.
The problem is, most of the privileges shown in users-admin are old-school Unix groups that aren't used at all by PolicyKit. So we'd have to support a completely knew privileges tab, based on PolicyKit. Not sure that will happen in users-admin.
Note that an easier solution would be to add an option to allow all users to install trusted packages, that would go in one of the configuration tools.