This one is in the category of “drawings that are relatively boring that I ended up making somewhat successful through putting down quite a bit of less boring paint.” Sometimes a mediocre drawing is an invitation to experiment more with paint… for other examples, see here and here.
I do the vertical lines shading a lot – especially in sketchbooks (for example: these drawings of my mom, and various selections from sketchbook 56, 57, or 58.) but I don’t typically carry that vertical grain over into the painting. Here’s one, but I don’t remember others. I just kinda decided to try it on this piece. It took a while to develop, but I think that the color turned out nicely.