Here are a couple more tiny faces I've done, perhaps it's practice makes perfect? No, I think it's knowing your facial planes and structures that makes these tiny faces believable. It's really not about "detail", it's more about what the viewer reads as detail. Both these ladies are around
9" to 10" tall.
"Lady in White" , Prismacolor on Wallis Pastel paper.
White is never really white, is it?