At present you can generate a user activity report for a single user. It would be cool if you could enter a group, such as atlassian-developers and get a report detailing the number of issues assigned to each member of the group, grouped by project. (IE: The current User Workload Report for each user in the group, in a long list of users).

Developer A (105 issues):
Project A: 103 issues
Project B: 2 issues

Developer B (230 issues);
Project B: 200 issues
Project C: 30 issues

etc.

Clicking on '### issues' for any user/project should take you to a a filter of the issues assigned to that user under the specific project. Clicking on the total number of issues next to the user's name would take you to a filter of all issues assigned to that user.