When applying and tweaking 3D Extrude & Bevel Effect, user has to manipulate light by precise mouse twitching over the small sphere.
It should be at least twice as big to provide fine control (I won't note this as separate request), but there should also be numerical fields to control the lights' position over sphere — angle, elevation, choose any.

Also, why Depth and Height values there are immune to document Units settings? 56.96pt is nonsense to me, while 20mm makes sense.