Push come to shove, if it was between the two options, I'd prefer they just brought Venus in rather than make our boys not our boys. As long as said boys aren't made to act stupid over her. (As if PD Mikey wouldn't be inevitable...)
But actually... Make her one of the turtle-like aliens so she's not just a gender bent version of the guys, but also quite different and so if she sucks then she can just go away after one film.
Though out of morbid curiosity I almost want to know what Hollywood female stereotype monstrosity a PD Venus would be... Also to make many male viewers feel weird about it because she'd inevitably be built like a Victoria's Secret model.
(Who's accused of checkin' out dem Turtles now, huh? Huh?? LOL)