For me it's the lips. In any other Nomura game they would be hot, in FXIV it looks like she had bad botox.
It speaks a lot about her design that me and many others still fine her visually appealing, but if Nomura FOR ONCE tried to go with the flow and take away the belts, the hammer and reduce the lips to XIV size she wouldn't look so damn uncanny.
She's the SE workplace philosophy in a Nutshell, become a celebrity employee and you can do whatever the hell you please.