What should the next theme be?

I would actually love something totally new, or even another occult pack just after we already got one, but I know that it's not like them to go back-to-back on the same pack themes, at least with game packs, but I don't think they'll tackle anything brand new quite yet. The vacation worlds are still quite empty being that there's only 2 and they'll prob look to filling it up some more.