Or it could be a common sitting pose in japan like seiza? The W pose does actually have a practical purpose; it's more balanced then a regular sitting. I didn't find it longer to get out of; and it definitely wasn't longer to get out from regular sitting on the floor for my sister. If a bunch of Japanese girls, who I kinda doubt are all super flexible, can do it then I really don't think anything of us can say you "need" to be especially flexible.
If you don't want to play a female Au Ra, that's fine, but I don't see why you are wagging your finger at Square Enix for continuing to do what they have done for all the females. All the girls have their "moe moe~" factor as you put it. And really we've had a good idea how the female Au Ra were going to be since 2.3 seeing as they used a female miqo'te as a placeholder for Yugiri until the Au Ra female model/skeleton/animations were finished.
