Ma'am, with all due respect, have you ever heard a guy ask for a male version of Lara Croft, Samus, or Chell that wasn't a complete douchebag? Didn't think so.
Not that I'm against having a female protagonist of course. Hell, there could be a different campaign for her that still leaves multiplayer with Crane players a possibility. Maybe pull a Dead Island Riptide and have her only appear in safe zones and cutscenes unless multiplayer's enabled.
The one actual problem I can see is debating whether or not she should have a slightly different ability set and/or personality from Crane. Another plus, however, is this would kinda make an opportunity to add another hunter in Be the Zombie mode.
Also, this probably should have been put in the discussion of possible features for future game updates. Just so you know.