You cannot have both ways.  Either men and women share one and the same human nature (the same human nature assumed by Christ at the incarnation), or there are two different human natures, one male and one female.

My understanding is that there is *one* human nature, even though male/female organs are different.  If you reduce personal masculinity and femininity to superficial external organs, you are effectively reducing them to sex objects, as in the exclusively male priesthood.