I should write as I see fit, without worrying about the prejudices of my readers.

If selling is the concern, I'm sure there will be plenty of publishers/editors/what have you who would ask whether or not a story should or can be retooled with a male rational at the helm. Stop worrying about appeal if this character is one that you want to write. It's so much easier to adjust a story to be more appealing later, rather than compromise your vision and creativity from the get go.