In all honesty, I don't know what you're on about with the big head... I've never ever noticed men to have a big head. If anything, to me a big head gives a female impression, because it looks like there's more hair. Not to mention that in theory, a larger head on the same shoulders should make those shoulders look smaller. There are gender features that people actually know and think about... but this is one that, I'm sure, makes a difference for no one's passing.