That is a very good use of gel pens.
Using their unique strengths to create a very eye catching drawing.
I have always liked reverse drawing. Light colors (chalk) on darker papers. It turns what would be a fairly mundane drawing into a neat picture.
The best i have seen in this category was a drawing where the paper was a skin tone shade of brown, and then using white chalk and graphite pencil, made highlights and shadows of a portrait.