These reports I like for some year end maintenance and keeping the instance decluttered. I run a Project Report for projects with the name 'untitled project.' When creating a New Project, people might miss-click when selecting a template and start a new project, hit the back arrow in their browser to choose the template correctly and not realize there is a project created for that miss-click. It can be surprising how many you find, especially with users new to Workfront. I always check the projects before deleting. They usually have a 'last updated date' that equals the 'entry date,' have no tasks, and a blank update feed.
This might not pertain to you yet only 5 months in, I run an active user report and sort by last login date. Helps uncover maybe some accounts for former employees that need to be deactivated and gives a view of how active people are using the tool and if some Plan licenses could be reassigned to and better used by someone else. I've seen a few instances of people swearing they will need a Plan license during implementation only to login twice a year.
Sr. Associate, LeapPoint