The Flagship

[Hinoto-no-Ryuji]

Here's the really interesting part... when you fly around that zone a little more, you will also see a cathedral and a handful of ancient ruins that seem VERY similar to those found in Cartenau, Qarn and Mor Dhona.

Well, the Cathedral, at least, is known to have been a structure dedicated to the worship of Sephirot, lifted directly from Meracydia. myahele has a good point in that the whole thing comes off as a showcase of Allagan Imperial conquest (although it's also an R&D centre); the Cathedral and its ilk are likely a part of that.

Anyways, on-topic, do we known when exactly Azys La came into existence? It certainly does seem quite different from Dalamud and the Crystal Tower. My current theory is that those latter two use older aesthetic sensibilities from the time when Xande first reigned; since Nihilist Zombie Xande designed them, he would have used an aesthetic contemporary to his time. Azys La and its Flagship, meanwhile, either predate or didn't involve Amon's pet project Emperor, so they use a more "modern" style.