The blue armour looks really blotchy. I found a method of painting thousand Sons/Night Lords thats really easy:
1. Spray model Black
2. Water down Enchanted Blue (or equivalent shade of Blue) and apply a thorough coat over the whole model.
3. Wash with Asurmen Blue (or equivalent blue wash)
For trim, I'd recommend Tin Bitz, under Dwarf Bronze. This would also look good of the banner, leaving tin bitz showing in the recesses.
For the bone, I'd recommend Caltharn Brown, with a drybrush of Bleached Bone, or Commando Khaki. Though you did good on the Power Pack skulls
Your silver areas look flat, so a wash of Badab Black would have great, with detail redone with Chainmail or Mythril Silver
The internal red glow sort of looks ok, but it also looks like you used too big of a brush for it. Repainting the face-plate. If you want to keep the red glow, try carefully drybrushing a darker red in the area.
I think thats all I can say. Of course colours are subject to name-change with the new Paint collection release, but hopefully the names I've given can give you a good idea of what I'm talking about.