In sculpt it would be very advantages to be able to make any kind of line or spline and pull or extrude a face from it.
This would allow you for instance to make the face some odd shape and then go back to model and extrude to that face for making or cutting a body/component.
I needed to make a cut in a body I created and the cut needs to radius at the top. the extrusion is also tampered and I have no way easily to have the cut form a concave shape at the bottom of the hole.