Been silently watching this thread in anticipation, looking brilliant so far =)
It's hard to say what colour to go for, initially I thought Purple, or a dark purple. Then I thought it'd add to the confusion of it looking chaosy. Also that the dark green of the snakes might get lost.. was thinking the same about black too. I reckon if you have a primary black colour with an aura of red around the emblem it would preserve detail and look pretty cool, the red would bring out the green and keep the focus I reckon. Or even an aua of yellow fading to black would be better. Albeit a lot more challenging
Hope in the darkness and all that jazz.
ED: In fact, thinking on it, the aura idea would also work in relation to the chapter symbol. Just more symbolic instead of purely iconic.