Mmm, thunder has been discussed in terms of another element, but has been generally disregarded as not really fitting in with the series style.
Well, there has been quite a few female Psys if you look at it- a lot of black capes from TPA2 are female, the tutors in Psy Academy are not all male at all (in fact, the only tutor we see in TSoG is a female). And Anya became Dean of Academy. Then there are significant non human female Psys (think Nelis, for instance).