Personally, not only do I want the bling without taking out a second mortgage, I'm also looking forward to stuff that hasn't been shown yet, but has been hinted at.
I'm not wild about the designs of the new cavern pieces. I don't LIKE a lot of complexity, it means I have to fumble through too many specific pieces to find what I want, and it limits what I can do (because in order to make something I need piece X, so to get enough of what I want I have to buy 15 of piece X, but that means I almost never use 10 of them because I only needed them for that one idea, so I have to jettison that idea, etc. etc. etc.) And I don't like having to bring 15 boxes out of storage any time I want to build anything. No, I much prefer simple engineering, with just "drop the pieces and put them next to each other" and minimal puzzling about this way and that. (Even though, I admit, finding unintended and unexpected ways to puzzle things together can yield exciting results, and sometimes the coolest layouts feature unanticipated combinations and uses of pieces...)
PLUS, on equal footing, I like my caverns to have a large footprint. A lot of twisty, claustrophobic passages may be realistic, and may look awesome, but it's not my preferred approach. It leaves a lot of table space unused, so it's inefficient, and it makes it harder to cram STUFF in there -- characters, monsters, treasure, objects. I want to place stalagmites and shrines and statues and purple worms and stuff in my layouts -- narrow claustrophobic spaces make it harder. I like the original resin cavern design -- larger pieces, open spaces, good balance between flexibility and ease of use.
We've been told that the new caverns will have a mix -- some small, puzzle-type pieces for complex builds, but also some larger pieces. I really really really like the bigger pieces. And to the extent I'm excited for KS6, it's for the promise of those.