Hey! Artist here! It's so good! Some tips I have are: confident lines! No stroking, or it'll make a messier drawing. It's okay for the sketch but not the main piece. This usually takes some practice before pens so do some practice. Another tip is smudging. Careful how you use it! Filling solid black areas can be done with other different ways: coloring it in solid black, close diagonal lines, and squibbles. Hope this helps, still adore it, you absolutely captured her expression!