Karen Gillan?! Nude?! Where?! But, back to sort of seriousness, maybe shaving her head was put out there by her, to add some nuance to Nebula. Your second question...? Yeah, I don't get the general attitudes or laws on that, either. But, I think I can work out a resolution to it:
If both people in the drunk hookup were all for it, and neither of them wanted to back out, then it's not rape in my eyes. Unless one of 'em starts doing something the other doesn't like, and doesn't stop, then that could be classed as a type of rape, but that applies smashed or sober. But the consent thing, while drunk, pisses me off, actually, because, apparently, as you pointed out, you legally can't consent to sex while drunk, so, in that case, why do anything fun while drunk?