Timing is everything. Ron over at FTW just posted about Roman style helmet crests. As my first real green-stuff attempt, I sculpted one of these for my Astral Claws Sergeant test miniature. I am not sure if I am going to do this for all of my Astral Claws, or just this one miniature. In Roman legions, the crest went front to back for normal legionnaires, and perpendicular to that (as shown on my sergeant) for officers. This would be a neat way to make centurions and sergeants stand out from rank and file astartes. It would be fun to see a squad of Astral Claws that did not side with their chapter. The minis could form a little diorama showing them throwing down their weapons.
The other mini posted above is the beginnings of my Corpse Taker. For those who have not bought IA9 and read it over and over again like I have, the Corpse Taker unit is a small Apothecary squad that removed gene seed from Astral Claws and non Astral Claws wounded. Basically they try to collect all of the gene seed they can in order to create more legionnaires. This is just about the worst thing one chapter can do to another. Naturally I had to paint one unit up! I used Fabius Bile's backpack thing along with regular apothecary bits.
In terms of color, I am still unsure how to paint white cleaning. No matter how smooth I think the blending is, the moment I take a photo the edge highlights of pure skull white stand out like sore thumbs. I plan to paint the shoulder pads blue and gold like regular troopers. I was also thinking about adding highlighted battle damage as well as blood spatters. These are gruesome marines after all.