Thoughts from seeing the full Endwalker's trailer:

The spiral shell "aethereytes" probably aren't normal aethereytes, considering that we've been shown a normal city style aethereyte in that unground area in Thavnair. I would wager that they are Sharlayan designed as bulwarks against those towers Fandaniel setup, using ancient knowledge that Sharlayan has due to living through multiple eras of the world with the whole truth of the calamities in tow, the whole while. Those Sharlayan nerds have been holding out on the world, hoping to be leftover to become full beings at the end of the Ascian's plans all this time!

As for why Thavnair has one, well I'm assuming that they have some sort of direct link with Sharlayan from older times, or perhaps it's some incoming new information we get tomorrow or in 5.55. Urianger speaks of a respite that was temporary, so I assume that's what the spiral-cut crystals are providing, and I'm also assuming that's why Sharlayan's capitol digs deep into the earth with its massive book pit.

Gotta have a book pit!

I really hope that the other jobs get some new animations for attacks, seeing how flashy the Reaper ones are going to be. The slices with the pale green aura are to die for, and I really think the older jobs could use some TLC upgrades. Particularly because only one or two people ever get to really switch it up in a raid group when new jobs come out, and if the new jobs are the only ones getting such delicious animations, then I feel pain.

I know I'm supposed to be like, "Yeah, get'em girl!" when Y'shtola does her sass walk in, and then slams her staff end on the Forum floor, but like... idk, the Scions coming off as know-it-all better than yous towards city leaders lost its luster long ago. While I'm not, you know, against what the Scions are for, cause obviously it is the good way to go, I can't help but feel like it falls flat for me.

Vrtra and Estinien :3c Azdaja when?! Also I'm pretty sure that's Thavnair they're defending, somewhere nearby, because the statue that gets destroyed is a dancer with chakrams, not an Ishgardian anything. At least as far as I know.

Zenos when he stands up look like they gave him a makeover. His nose is very straightened out, and his jawline is different. His face when he stands up screams HIMBO. That coupled with the character line up cover art has me suspicious that they really will pull some sort of Golbez-like plotline with him.