Eden: Sure, I was just thinking that
some items could be useful for both, and you might not want to assume that someone's going to use it just for Mack-style characters. This is easily the nicest sprite-creator that I've seen so far, so I'm tempted to start porting over some resources from the Famitsu generator to see how VX RTP-sized sprites could work in it, in which case the size differences are minimal at best between genders. I was just thinking that you could create another "Unisex" folder for each category that would be automatically included in the drop-down boxes regardless of the selected gender.
The gender idea isn't bad, though, I don't think. Going entirely unisex could clutter up the interface like insanity if someone has a lot of assets, and it's easy to segregate them into male, female, or unisex in my opinion.
In any case, your program is awesome whether you decide to create a unisex category or not. That was just one of those thoughts that sprung to mind as soon as I started looking at how things were organized, and if there's anything that I'm fairly confident in, it's my ability to organize the hell out of things.
EDIT: Correction: I'm good at organizing things digitally. IRL, I'm a mess.