No nationality

In the full search there are many cool features, although I can think of one or two options I'd like to see. However, one I'd love is to be able to search for girls sans nationality. I've come across a few that with a couple of minutes of research, could fix. It's sort of enjoyable actually, the challenge! Can the first option on the drop down list be say '-' (or indeed, for other fields, for other research/search)?