I don't see a problem with the black brushing. I like the flow here. Depth kinda' works, but the right side lacks it. The text style is pretty common, but used nicely here. Lower the stroke of the black border. Too big ftl. Soft brushes are good. Other than that, what am I to say? Good job.
I also like the depth thing going on, split has a point. What I miss is adding reflection effect to the figure, most of all on the parts that's supposed to be metal - I say you should make simple strokes or red (possibly black) on the metal, like a highlight thing. Metal works like that, almost absorbs the surroundings like a mirror would. Not much is needed, but right now it's just too yellow imo. Very good job on everything else, I think.