Here's what I'm thinking for Necrons. I'm keeping the green energy effects, and I like the idea in the codex for the white faces (shown on lychguard) so much, I'm making it army-wide. Bronze-rusty main body, aged cobalt-coloured embellishments. The crystal sticking out of the snow is literally a snipped bit of sprue used to hold the Necron Warrior gun barrels.
Let me know what you think.