Great thread! I use pretty much the same method, but I've been too lazy to make a thread.
If you don't mind I'd like to add an optional step.
Once I have the shape that I like, I like to see how different materials would look on a particular blade before I get started on the actual scales.
If you look around online it's easy to find stock photos of nearly every type of wood. Then select outline of the shape layer of the scales, then copy/paste. Then go into blending options and add bevel/emboss and contour.
Here are a few quick and dirty examples using your blade and shape. Usually I would play with pinning options as well at this point, but this is just a quickie :|
Amboyna burl, Bocote and bloodwood;