I think these guys are just making stuff up 'cause there's nothing to complain about.
In my eyes, the shading is quite amazing, it's perfect.
It's very original, and usually, I hate heads with like playes or just metal looking stuff on, but you've done it really well.
I just noticed the only thing that doesn't look really good, it's the edges on the thing on the back, they look too sharp.
Ooh and if you really want, you could make like sort of damaged skin around the plate thing to show it's been stuck to it's head.