Cool, I'm experimenting with something similar.

I thought I would try laying down a range of basic skintones across my horde of Italians, and work up from those the way you described.

I feel like I'm going against the grain (all those guys on the internets) by assembling the figures, heads and all, before painting. It feels more natural to me to work the complete figure, picking up on the body language, pose and uniform as I work. I do leave accessories to the last though, as they tend to get in the way.

Thoughts?