I've been always  striked at how powerful the Line is. How much volume it can contain in such a simple element. Just by giving the right pressure and the right angle at the right place it is possible to perceive everything. for almost ten years I've been looking for the perfect (hand drawn!!!) line. Yet I still feel I have a very long path to go.
Moreover after achieving this I could go to the fantastic worlds of Shapes, Values, Colors...(sigh) I'm so screwed...