I think you have a good choice of colors going on.
Its difficult to judge by the last pic you uploaded, but compared to the fleshtones, the steel trim and armor/weapon color seems really flat, and everything looks unusually glossy. What type of paint are you using, latex or enamel? It might be worth doing a slight ink-wash on the weapons especially, mixing a dark brown and a black or dark gray, and shading down the crevices in the weapons. And then maybe a quick metal highlight dry-brush on the leading edges of the blades and barrels. the same sort of wash also works wonders under chins and in mouths to add depth.
Feel free to ignore me if I'm telling you stuff you already know or did since that last pic!
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