KF female skin will be DLC eventually.
My point being, if you you were not given a choice of skin, no one would even bat an eyelid. Provide the smallest amount choice and suddenly people want every option covered.
And as games like Brink or TF2 have shown, customisation just ruins visual design. Making it harder to identify what people are.
Ok so ACM is more co-op, but it's going to be a given that you are going to be playing mostly in the dark and/or not looking much at the other marines (who I might add are wearing a uniform), so who gives a shit what you look like, or what gender your char is. It doesn't effect gameplay so why have it in the first place?
Lair Keeper - Long Fang - Pack Keeper