I would make his eyes Green, and maybe a green belt with the Omnitrix badge on it or something, but I prefer each alien having their own signature color pallet, instead of just looking like their wearing a Ben10 onesie, which is my main critique of Feedback. (see, in my head-canon, Feedback has bright electric-blue skin and golden plug-thingies, and also golden boots the plug-thingy stuff in his soles, which he uses to run up walls via manipulating magnetic electron-attractions and stuff. He still has green eyes and the Omnitrix badge on his chest, but he has own color scheme beyond that.)
