Well, that's my personal opinion
Cause, the whole texture we're "abstract" and if you add some "cartoonish-thing" into the head, it will only made the head looks terrible.
Thanks everyone. The vertical lines on the back were meant to vaguely resemble combed-back hair. Originally I wanted them all perfectly parallel and running straight down, but mapping the top of the head is a bitch, hence the slight "v" look. Made a different version of the back: