As with many, it doesn't much matter to me unless I deem them to be more apt as one gender or another.
Machamp, Graveler, Alakazam, Steelix, Crawdaunt are some that- to my mind- are just male. Inextricably.
Ninetales, Gardevoir, Dragonair, Mismagius, Espeon, Lopunny are a few that I have great difficulty seeing as male.
It's stupid, but it often does take priority over anything else whether I choose to catch it or not. I remember spending a few days kicking around Hoenn trying to find a damned female Ralts.