Enhance JQL to include User Properties

I would like to see JQL include search / selection of User Properties. We need to see time spent on project(s) by members of a Team (e.g. Developers, Analysts, Architects,...), or by personnel from outside Organisations. (e.g. supplier X, supplier Y,..). This is significant in being able to track time / costs and reconcile with supplier invoices. The benefits of being able to do this would significantly aide and simplify reporting, give quick and visible feedback by using the selected data in dashboards.

We are not alone in having a mix of internal staff and external suppliers providing staff for project delivery. We can add 2 properties to all users, (it has to be done by hand it is not possible to add properties to all users at once), "Organisation" and "Department", and fill in the values accordingly. Then we would like to use (the excellent) JQL to select / search on those properties.