What I mean is that, it doesn’t really feel like you’re underground. Everything is this vast open space… I get the whole gameplay aspect, but I feel like there is too much of a lack of caverns.
Honestly I’d like to see another cave area with ground only mounts like undermined. With lots of bridges and caves…
closed spaces wouldnt be that fun and the art team wants you to marvel at the special thing they built
I would not. And the point was to make it more open and expansive in some places because people hated Zaralek.
Azj-Kahet and Ringing Deeps are plenty underground for me.
Ringing Deeps feel cavernous enough to me.
Possible the next zone is either the home of the Harronir, Arathi kingdom, or the secret entrance behind Dornogal. However you didn’t hear it from me. 
Secret Tunnel!
go watch some extreme cave diving videos. You will change your mind on claustrophobia real fast.
Needs an Agartha / Land of the Lost zone, that’s sort of what I was expecting with Hallowfall and their artificial sun, but instead we got another Drustvar with characters like Faerin that are more appropriate to games like BG3 or DA: Veilguard. Since this is a Titan / Old God xpac it’s the right time for another Un’goro Crater / Scholozar Basin type area as well.
Underwater cave diving is my worst nightmare
I cannot comprehend why anyone would want to squeeze through a super small tunnel while underwater and risk getting stuck
Then maybe they shouldn’t have made an entire xpac around being underground lol. Instead they were like “let’s go underground, except make it feel like we aren’t”. Like way to not commit to the idea. 
Oh how they have quickly forgotten how claustrophobic that zone could feel lol.
There is also nothing like flying into hallowfall. No matter how many times I enter that zone, its such a crazy feel and experience to look around.
I’m not disappointed at all, honestly was happy with how well the zones turned out for being an underground expansion. I prefer outside, airy open zones mostly.
We’ve got not just one, but three vast underground caverns in TWW. Four if you count Undermine. They obviously had to be open enough to allow flight or mounts in general. 
Delves are kinda what you’re asking for.
But that’s instanced content rather than zones you can just explore
tiny cave mazes are very confusing to navigate with the map
no im sick of them
The Harranir claim their Goddess is inside Beledar.
Furthermore the West Studio Concept Art for War Within(https://www.weststudio.com/project/world-of-warcraft-tww) has 2 Pictures of Eldritch Horrors inside Crystals.
The only thing I could find about this is the questline we did for that titan memories stuff. Are you referring to something else?
Their concept art is actually what led me to ask this question. Lots of neat stuff in there. Like the airships using crystals to fly… I feel like that would have been more interesting than just a regular airship… specially in a zone all about the damn crystals. It feels lacking in that aspect.