First of all, you're a great artist and have much, MUCH, more knowledge than I on the subject.
I would be totally fine and enjoy the site of the female Pandaren if they were to look as you stated. I doubt I would play one, but they don't look bad overall.
Just for the sake of counter-argument, not all of the races follow that model exactly from the untrained eye. Or maybe because they make some of them hunched over it allows them to share the same height. I'm pretty sure that Orc and Draenei don't share the same height and head sizes, though don't hold me to that since I've never actually broke out the pixel measure tool. Of course their measurements are still based off the "head" sizes that you talked about, just with different measurements. It would be nice to see the gender differences for more than just the Dwarf, Blood Elf, and sketched Pandaren.