Still, it'd be nice if someone could answer the original question, so anyone else clicking on this thread would be able to get an answer.

It would seem that percentage of females is mostly a matter of luck, since a clone taken from a female will grow into a female and pollinating a female with a staminate female will give you feminized seeds. I've heard that if your plants become rootbound early on, they are more likely to become male, but I can't verify this, and I'm not sure how this would work.