The portrait sketch above turned out OK. I'm using the technique of mapping out major features with faint dots. Even if you move stuff, the dots aren't really noticeable. So that works well. If I had done it in pencil, there are a couple of things I would have altered slightly, but I am still practising quick pen and ink sketching, where every mark is permanent! Staedler 0.2 felt tip pen, and F felt tip pen. 4 mins for most of it (which is as long as a person usually sits still for!), then the usual time spent doing the toning on the hair, which can be done later. This is about 15 cm high, so medium sized.
It wasn´t quite as true a likeness to the person as I would have liked, so I did it again. The pic below was a really good likeness for the person. I'd prefer to get it right the first time, but it does often seem to work best the second time.
Gratuitous photo of Wainui Bay, South Island, New Zealand