I'm keeping it simple and sticking with the recommended GW recipes. I've got the chart I've attached here on my wall for reference. The blue is the one that starts with The Fang, Nuln Oil, etc. Their fur starts with Mournfang, Agrax etc.
For most colours I've been applying another light layer of the base colour after washing, before the layer colours. It just makes things look a bit smoother.
To be honest, I've switched to a more traditional red for the cloth. Half thinking about painting duardin next using the Fang recipe prominently and didn't want the armies to look too similar.