This is great. I spent ages trying to create a pencil effect in Blender a few years back and was amazed at how hard it was to get something realistic looking. My favorite example that I found was this mouse: https://www.youtube.com/watch?v=FrZxgWqCF-w and https://www.youtube.com/watch?v=XJ82ifA6nlk and https://blendernpr.org/celestine-breakdown/ Sharing in case there's something in there that will provide extra inspiration for your work.

Thanks for sharing! Really interesting to see these are quite a different look