I like it but the white spaces gave me the first impression that there was missing textures. The yellow streaks remind me of tribal tattoos, so for the back you could look at some cool back tatts for inspiration. I like the minor asymmetric details but I'm not sure about the white areas. In some places it doesnt look right, like on the back side of the pecs and back of the thighs. It's really up to you but the dark piece between the pecs and neck would probably look better as white and the only thing about the white space on the thighs is i imagine they're supposed to be pants and it's just an awkward feature. Hopefully that helps