Filtering rules and reports by user attributes (User Groups)

When I build rules and reports I'd like to be able to select User attributes other than Name and Email and filter on those items in order to better manage teams within the Gainsight user base at my organization. The current system only allows us to add or exclude users in a field one at a time, and this can be problematic in some circumstances such as CTA assignee name where any user could be represented.