I have to assume the Rootlands & the Coreway will be combined into one season. Because it wouldn't make sense for either to show up later in the saga. Maybe we go back to the Coreway as the finale of the saga....but why would the characters wait that long to go there. They want to go there right now.
The Coreway could not be fixed in time and then Xal makes her gambit for the Sunwell? But we still don't know if we're protecting Quel'thalas from an invasion or if we are defending it from an invasion.
It does feel like the Coreway has to be mixed with the Rootlands, but that would be strange as the Rootlands and the Haranir seem to be a secret society. The Rootlands really feels out of place in the trajectory of the story, but I'm sure they'll do it well.

Surely the Beledar will have some role in the story, right? No way they just completely ignore it.

I think a general consensus so far is that Beledar will be the inciting action for Midnight as the Dark Heart was for TWW. There are just too many signs pointing to Beledar, the Arathi and the Light for it to just be a set piece.
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I suppose this makes sense. I wonder if we'll see Thraegar in 11.2 then.
Well, for example, the writers justify your Turalyon's long absence from anything important in the main plot by saying that he is the regent of Stormwind. He is supposedly too busy. Meanwhile, Jaina is capable of being everywhere at once. She is the leader of Kul Tiras, she is the leader of the Alliance army on Khaz Algar, she found time to resolve the conflict on Arathi, and now she will also be rebuilding the Kirin Tor. Don't you think that's too much for just one character?

After dealing with the Black Blood again I would kinda love to have the final raid to be us venturing into an Old God corpse to destroy the source of it, with an aesthetic like that one section in Ny'alotha, interspersed with ruins/structures the old god grew over.

You make it seem like all of these things happening at one time, are still happening at the same time. It's not hard to believe that the passage of time occurs inside of the game. No I do not think it's too much. The story is progressing. This comes off as you wanting it to be too much.
Yeah, sure, but that was ages ago, and were crawling through a hive , not really through C'thuns body.
We had Black Wing Lair in Classic and Black Wing Descent in Cata.
We had Ulduar in WotLK and Antorus also used titan aesthetics.
I don't think "having similar themes and aesthetics about 20 years apart" is a reason not to do a certain raid.

