Honestly you might see me there because that's the closest regional, usually, from where I live. I think that it wouldn't be a bad idea to wait until worlds is over to decide on a deck because unless a deck involves forest, it could probably carry over pretty well into expanded. I've seen some hype already for Alolan Muk + Hypnotoxic + Serviper + virbank and a couple others. My friends though are excited about Night March making a comeback. Really it's hard to say, and like I said earlier, I would just let the professionals fight it out at worlds, and once the burning shadows meta has been established in standard start thinking about how you can work it into expanded.