In a certain way Van is the ultimate gaming hero because he fights against the stupidity and destruction of the Trails series looming over Zemuria. I wonder whether Joshua will be happy that Karin was going to die anyway and that their suffering was an irrelevant footnote in the Falcom circus.

Well, it remains to be seen what kind of lunacy they pull off with Water and Wind. Probably in a single arc and maybe they're fused to provide the drying/erosion in the East.

The problem is that it needs to get even dumber and more devastating than the current freakshow and the bar was set pretty high.

If we think back:
Space/Mirage were mastercrafted stories which told very intelligent narratives in a non-haughty manner and were able to reach you because they were built around credible individuals with a down-to-earth perspective.
Then it became 3D and of course they lost their shit. They merged Fire and Earth into this uber-evil bastard who conveniently produced a curse, that had even the guys behind Hamel be actually cute and nice, just this evil bastard and the curse made Erebonia look bad.
So after that shitshow was over they went on to Time and drew some bigger and more apocalyptic asshole out of their hat instead of, for example, having Roy look for the Sept-Terrion to revive his wife and save Agnes. Now seemingly even Ouroboros' name and iconography is just dedicated to the shit box.
Given that everything looks like the climax of Zemuria's destiny, how do you go beyond that?

Here's an idea: The Grand Odyssey CD has 19999"-XXXXX" in its name. If that has a meaning maybe the Eternal Recurrence Plan is meant to corrupt the Reset and transport everybody (guiding fire) to an entirely new 20,000 Zemuria.

If the last Sept-Terrions are in the South and East, that would otherwise force them to set the last games in deserts and Chinese wastelands, so I expect they go for a transformation of the world.