Lord I hated shading at first, and I NEVER shaded, you can see that in any of my older work... BUT... once you begin to shade stuff... even when you feel like your over-doing it, the drawing really begins to get some life to it. So definately shade stuff, BUT, remember to shade in the right direction, as the lightsaber is an obvious light source.
Another tip, it helps me to draw a box out and then draw whatever I want to inside the box, this keeps everything clean looking for some reason. You can also simply tape a box so that a true box doesnt detract from what you drew in it, but the drawback is that tape traps dirt if you take a while to draw, and also it may tear the paper depending on the paper texture and the tape itself.
Great drawing so far, like-ness is near-perfect.