Despite the fact that many guys do go the buzzcut route, the general rule is that women get their hair cut the same length all over (if it's short), and for men, the top should be longer than the sides and back. However, that said, you've got a pretty feminine face. I assume you know this, and I hope I don't make you feel bad by saying it. It honestly may not matter how you cut your hair... you may just be stuck with being pegged as a girl or simply androgynous until you're able to get on T.
Dig the mohawk, though. Might look even better in neon.
SD