Extend the Restricted Fields with a "allowed" option

Who would benefit?

Superusers / admins

What impact would it make?

Less complicated maintenance

How should it work?

Add the option to allow a field to be edited while it belongs to a category which is set read-only.

Why is it needed?

Today my example category has 20 attributes which are logically grouped in a category because of the nature/purpose of the attribute. That category is read-only for a certain user group.

Now I have a new attribute in that category which should be editable for that same user group. The only way to get that done is remove the restriction on the group and add individual restrictions per attribute which is quite some work. Or alternatively split the category into two (one read-only, the other not) but that creates unnecessary categories just for that purpose...

It would be great if you can add this "exception" whilst keeping the read-only restriction on the category in place for easier maintenance.