For Blender 2.8, we want to improve the workflow for adding drivers. Here's how:
# When the user right-clicks on a property and adds a driver, we display a persistent Add Driver floating popup.
# While open, all of Blender remains responsive, and the user can select any object in the scene.
# From the popup, then can select a property to use as as a driver. No other steps are needed.
Optionally, users can then set a multiply and offset value, and add additional driver inputs. They can also click the Open Driver Editor button to open a Drivers window,