On second thought, there are some Pokemon species that I like to have as a particular gender. For instance, I can't fathom the idea of female Charmander/meleon/izards... it's just a weird image to me. Just like male Gardevoirs weird me out.
Gender, nature, ability... all that crap I don't really care about when playing the games. Never really play competitively, and I always find it weird how all of the trainers have Pokemon that are the same sex as they are. Must be some reeeeeal misogyny and misandry going on in the Pokemon world...