Seeing a single percentage of progress for an Epic is useful, but it would be eeeeven more useful if I could see what percentage is in flight. Or alternatively the number of stories done, the number in flight and the number complete. Example: it could be that an Epic has 10 stories within it and 5 are in the current sprint, a 50% progress bar does not feel like the right representation of this epic. 50% progress (50% in progress) would be more valuable to me.