I absolutely love your scheme! I'm thinking of starting nids and was thinking about doing a pale blue like yours. Mind sharing your recipe again? I'm sure it's already here somewhere if I read through more thoroughly...
All undercoated with vallejo grey primer.
Skin colour is guilliman glaze over the primer (contrast before contrast was a thing, now out of production I hit up all my local hobby stores and bought about 6 pots of it!), drybrush in ulthuan grey.
Chitin/bone armour is ulthuan grey over the undercoat, agrax wash, ulthuan grey drybrush, army painter brain matter beige as an edge highlight.
Talons/claws are vallejo black, then the fade is airbrushed in using sotek green, temple guard blue, baharroth blue and white scar. I then edge highlight each section with the next step in the progression, ie, Black highlighted with sotek green, sotek green highlighted with temple guard blue and so on.
Really easy to do. Quick, simple and effective.