Make all roles available when searching for relationship records

We've noticed that in the first relationship screen when you're doing a relationship query that the only global roles search available is 'all roles'. However what would be very useful is that that role option for all records give a list of all the roles available in the various relationship types - a global list we can choose from. Otherwise we have to conduct separate searches for each role in each role type - this is unnecessary from a design perspective - and time consuming for users. Example: role: nurse. We have that role available for members across several relationship types. Now to find that role, we have to conduct up to 3-4 separate relationship type/role searches to capture all the records that could have x role.