Excellent work wayniac! That's exactly the idea I had for painting my Death Guard models if I ever end up getting any. Did you hand paint these or use an airbrush? I use an airbrush for most of my painting now days and I was planning on painting them in their heresy colors as the base and then airbrushing thin layers of agrax earthshade and nurgles rot to get them good and gross looking.
Handpainted. I have an airbrush but every time I've used it it's clogged up. My recipe is pretty simple and effective:
* Zenithal prime (black all over, gray at 90 degrees, white at 45 degrees) ++ probably not really necessary
* Basecoat armor with Vallejo Model Air Aged White (needs a few coats, I should have basecoated with bone or light tan first), green with Citadel Castellan Green, bronze with Vallejo Game Color Brassy Brass, steel with Vallejo Game Color Gunmetal, horns with Rhinox Hide (any dark brown will do)
* Drybrush armor with Praxeti White
* Skin on champion is Rakarth Flesh, drybrush of Pallid Wych Flesh, washed with Athonian Camoshade to give a sickly tinge
* Wash various open sores with Druchii Violet
* Wash entire model with a very watery Vallejo Model Color Smoke (I used a 3:1 ratio of water to Smoke, something like 5 drops of smoke and 15 drops of water, you want it little more than muddy water, this makes everything look dirty and oily.
* Apply nihilakh oxide to brass, typhus corrosion + ryza rust to some metals