It depends on the type of girl you want to attract.
If you want the slightly dirty girl (you know the ones who have bed head, chipped nail polish, tight clothes and chlamydia) go for the long hair/facial hair
If you want the pseudo "nice" girl (the kind who wear ugs, yoga pants, a messy bun and tell anyone who listens that they just want to be "present") go for the clean cut look
If you want a normal down to earth chick, buy a man bun and grow a full beard...
*ok, my serious two cents: I prefer men to have long hair (absolutely NO mullets though) and as much facial hair as they can grow. Full beard. That's just me. I like very male guys. None of this metro sexual or army brat shit. Grow your hair. But take some time to style it. Don't just let it hang in greasy strands. Use product.