We do internally developed software capitalization, and our time tracking must align to the epics teams are working on (in our world, epic=project). Because of this, we require all issues to be tagged to an epic. Sub-tasks cannot be viewed in the Plan mode, and therefore cannot be tagged to the epic. In addition, when I create a sub-task, it is not inheriting the Epic link from the parent.
This causes our time reporting to create orphaned hours for sub-tasks which have no epic.
Please expose the sub-tasks in plan (or make it configurable), or ensure the epic link field inherits the epic attributes of it's parent!