Yea, I know you mentioned it already, but the cape to me is what's throwing it off. The robe(s) appear pretty wide too, but that's more forgivable assuming the cape is placed on there correctly.
As for the helmet, I'd repaint it if at all possible, like one mentioned, the dome. If you do go that route, I'd also thin out the return edge along the front part of the dome that flairs out along the sides, as those look pretty wide and sticks out like a sore thumb to me.