Looks like the scale in my head is almost exactly the scale of the toy Robby. This is totally unplanned, as I had started on the paper version before I purchased the toy version. I didn't have a real scale in mind, except for large enough so I could work with my old hands and fumbly fingers, but small enough to print on standard US letter cardstock.
And speaking of scale, my son bought and installed this display shelf and lights for my birthday last month. You can see Robby is 14 inches, so in comparisn 'ol Nosferatu is a big boy!
I don't have a clue what scale he is...