Funnily enough, there's not enough customization at character creation.

[Shioban]

You can please some of the people some of the time, but you can't please everyone all the time .............. or something like that. Besides the cat butt thread and request for long hair (which I'm sure is in the near future), I haven't that many threads complaining about lack of features. But give it a couple more patches, and maybe they'll develop the Mario stretch-your-face feature eventually.

You clearly haven't seen of heard of the designers for FFXI and or FFXIV.

They're very very particular in terms of restricting the look of things, giving people complete freedom is something they're known for.

For example when Yoshi-P asked (whichever team) about having the players ride without a saddle on the courel mount, the designers refused. The consistency of the world and how things look is extremely important to them.

Another example would be the upcoming vanity system which will restrict 'vanity options' to certain pieces of gear and class-restrictions.
(EG ; A paladin won't be running around in Allagan gear that's been vanatied to look like the Black Mage Artifact Gear)

Body sliders (especially fat, shoulders, leg length) affect the over-all look of gear so this would never change, adjusting things like height is easy, however their current restrictions make it an easier system to expand upon (in terms of creating new gear/hairstyles, weapons). (These restrictions also helps reduce memory consumption and packet transfers for character data. The less data the faster it sends, having complex information about body/head-size values increases this).