Being able to the track and manage epics, features, and requirements on the workflow/kanban board at the same time would be a huge productivity gain for our teams. We constantly have folks who forget to update the status of an epic or requirements associated to a feature, so some is lost in team meetings determining whether or not the status should be updated for item (which affects how much time we can actually spend discussing what needs to be done, or having developers actually developing. In some cases, we even have a missed requirement because they don't "jump out" on the work in progress board.
Pivot reports are fine for displaying all this information, but they aren't the great for actually making quick updates to the status or assignees (the drag & drop functionality of the workflow board is key!). Additionally, it can't be configured without showing nested fields (e.g. assigned to & status).