I said from the get-go with the Indestructibles that I wanted the characters to be written as gender-neutral as possible (avoiding all stereotypes so that you might easily recast any character as male or female and not have it be jarring). I don't know if I succeeded, but it is fascinating to see someone do this on a larger scale. Particularly because I feel like it'd be pointless to do this with the Indestructibles--hypothetically, the story should read the exact same if you swapped all the pronouns and made Billy into Billie and Emily into Eobard and Jane into Jack.
I mentioned this over on Facebook this morning and got a few funny and interesting comments. The first was that I could do a "Crisis on Infinite Earths" style story with the Indestructibles, and I thought--now that's a story for somewhere down the line. They've already traveled into the future, so they know alternate versions of themselves exist. Why not an alternate timeline where they were the opposite gender? I feel like Emily would get a huge kick out of it.
The other suggestion was that Kate might have been an even more interesting character as a male ballet dancer instead of a female dancer. I love this idea. I wrote Kate as a female character because she was inspired by several real-life dancers I knew who would perform through broken bones and other ridiculous injuries that would send "professional athletes" to the disabled list. Those dancers I've known were all women, and so she's kind of dedicated to them (though her personality doesn't come directly from any of them--they were all less anti-social). I'm legitimately curious what a male version of Kate would be like. Though the answer to that might simply be "Alley Hawk" or even "Batman." (Dream comic: Batman and Dancer get into a fight, and she's so impossibly determined that he brings her into the Bat-family.)