Thoughts for the next 8-man and 24-man raids or raid bosses?

Okay, so, while SE claims they wont do another raid in the same sense as the Crystal Tower, with direct ties to FF3, I think its clear they will find a way to pay homage to anything Final Fantasy they can, and why shouldn't they. So here's the question.

What do you think the next Raid or Raid bosses could be? And what would you like to see?

I personally thought that something similar to the Tower of Babil would be cool, or possibly Memoria, or if Hydaelyn isnt feeling well, a "Great Crystal" raid. Bosses I cand really think of other than bringing in the 2 sets of the 4 fiends, though one set would be slightly incomplete, since Tiamat usually counts as one, though I'm sure there is another name they could use. Any thoughts?

More raids that focus on strategy. Less of the beeline boss rush.

Less linearity would be nice too.

Mob mob boss mob mob boss mob boss boss formula is stagnating.