You seem to think that a few people (that by the way, tend to be always the same) on a forum are identifiable as anything else than a very limited niche compared to the big picture of a game's userbase.
"done with the design" can mean a whole lot of things. It can (and probably does, since no company scraps work in a very advanced state, unless it's not satisfactory) easily mean that they have some character design sketches in place. Do you know how much work comes after that to implement a race/gender?
Creating all the design variations, equipment (because equipment models aren't just textures slapped on a generic body. every single piece of equipment needs to be modeled on each body type or head), expression, voice files, animations (involvig all the motion capture work), syncing of animations, playtesting...
That's a crapload of work, and that's not something that can easily be done "on the side", especially in a game that involes such an high level of visual detail as FFXIV.
It would most definitely take a large amount of resources that shouldn't be taken away from much more urgent content that can be enjoyed by everyone.
WoW has character models and skeletons that are on a whole different scale of complexity as opposed to FFXIV models. Basically it's like comparing the sketch of a 5 years old with one drawn by Leonardo. Less complexity = easier to implement changes.
The most prominent cause is, probably, the fact that they had several co-marketing deals with PC brands in Japan since several months before launch. Delaying the launch would have broken those deals, and I doubt the executives of the company considered it an acceptable choice.With all of the things that are in the works, I do wonder why Square Enix chose to release FFXIV before they were ready.
Mind you, I'm all for muscular or athletic women in games. As a matter of fact, I prefer them to extra-lean ones. But I'm aware of the level of work involved by the introduction of even one race/gender combination, and I can easily guarantee that it's a much, much more complex process that some would like to believe.