Ah. Well, to be honest, I'm more versed in comic book pencilling. I don't do much shading, because the pencilling I do is meant to be inked and colored over. I'm still green when it comes to adding shadows and such. Most shading I do regularly is the kind used for pseudo-color (i.e. that bad guy picture on page 1). I tend to use hatching more for shadows and such.
Ya, I do get that comics vibe from your work. (And I'm still VERY jealous of your clean lines)
Hatching…that's another thing...
With pencil, hatching is more suited for refining and detailing existing shadows. Using hatching to actually define the shadow itself is more common with pen/ink. (Though you see it in preliminary pencil sketching too.)
The edge that graphite has over pen, is that you are able to shade using a variety of tips...you can use a blunt point, chiselled point, or the side of the pencil. (Not just the tip)
I mean, if you're using pencil, I think you ought to experiment more and go all out, rather than limiting yourself to pen techniques.