The big "world changing" event is recreation of FF5 end game event when ExDeath pulled some parts of the world (with whole cities!) to the Void. It will be similiar in FF XIV. Maybe some locations will be unavailable during time between 6.5 and 7.0 (like your favorite West Shroud!). Maybe we will see just black void orbs approaching most vital parts of whole universe (not only our world but First as well). I choose to draw Mor Dhona because this is place that likes to change, if you know what I mean :->

What is happening?

After 6.2 MSQ we know that whatever we do, it has no meaning for Golbez. For him our win belongs to "task failed successfully" cathegory. What we exactly do, and we don't know about it, is we release Enuo from Sealed Temple in Thirteen.

Enuo is historical character from FF5. We do not meet him in game, we only hear about him (with exception of GBA version of game). And in reality we do not know much bout him. That gives writers some really cool opportunities to development this character. What we know about him is that he has nearly godly powers. He was immortal, but he choose to trade it for control over Void. He was defeated by some guys with 12 legendary weapons, but he never killed. He was prisoned in place that was ending point of both light and darkness.

In current MSQ you can hear from Zero about big war years, years ago. It was battle against the Enuo.

The seal that keeps Enuo in prison is powered by darkness. Returning light to Thirteen will nullify it enabling Enuo to escape.

I don't know exactly what Enuo's motives for his new life can be. But because there is no longer immortal, and still controls Void, he can use it to trap everything in it. If I understand correctly, darkness activity slows flow of Aether. If you have controll for Void you can use it to trap everything in one moment in time. So you can still play as immortal god even if you are not technically immortal.

Next job

This one is obvious. Introduction of light/dark magic's new components focused on time (passivity of light and activity of darkness) gives you smooth way to introduce new job based on this components: Time Mage.

As you can see, IMO next expansion will be influenced much by FF5. It's because of three things. Void motives, order of older FF's influences in new expansion (FF3 in Shadowbringers, FF4 in Endwalker) and last but least: it gives this amazing opportunity to make intro cinematic containing this sweet, sweet, sweet main theme. Because, you know, You always make an expansion just to include your favorite music tracks xdddd

This is just my take. Maybe it will be totally different. It's just nice feeling to "hit" with prediction and feel like you have IQ or something.

I hope you appreciate my drawing xd