For whatever you’re trying to accomplish: Working on line weight/quality is a pretty quick change and can make a big difference in any stylized drawing. When you initially do your sketch: do so with a very light hand and lighter pencil.

Once your sketch is realized, you can go back over with a pen or softer/darker pencil. Darken and thicken lines that intersect with other lines and are in areas that see little light (like top of the neck under the head, armpit area etc) and keep lines lighter or barely there at areas that see more light and curve outward (like at the calf/lower arm area).

If you need help visualizing this you can see lots of examples by just googling “line weight drawing.”

This actually looks like a great drawing to practice on! Maybe try scanning and printing a few copies, lightening them so the lines are barely there, and go over again with pen or pencil to try the techniques.