If you're going based off TB colors I would try using a Shaman or a Cobra, it would seem like a win but anything could go on a robotic head. A Blue of any sort with white and gray.
I truly love the start of this and I'm expecting it to end just as it started.
I would obviously hope it doesn't stay symmetrical, or it would devalue any detail you already have. Only one problem I'm seeing is all that open space, unless it's to balance the rest of. Hope to see it when it's done.

A rating wouldn't do any good, but I personally love it. Keep up the good work.