Reference lines today have a static label. Ideally, they would be dynamic like master items, sheet names, chart titles, etc.
In my use case, I have a suite of measure options tied to the Variable Input dashboard visual. The chart shows the dimensional values while the reference line shows the average or total. However, the reference line label needs to be able to update to correspond to the selected measure.
“Perfection is achieved, not when there is nothing more to add, but when there is nothing left to take away.” — Antoine de Saint-Exupéry