Hi,
What I would like is an option when creating an angle dimension to create the dimension by using one of the selected line, and a "fake" line that is perpendicular to the other selected line.
First, you select both lines, right click, options, perpendicular :

Then, it creates the fake perpendicular line using the selected line that is further away from the cursor. So, basicly put the cursor between the "new" line you want and the correct selected line. Simply click to create the dimension like any other dimensions.
The end result would look like this :

Right now, the only way to have a dimension like this is to create a sketch in the view, project a geometry, create a small line, and then dimension using that line. This is extremely time consuming when you have multiple angles to detail. And 90% of the shops we work for want their angle cut dimensioned that way.