Yeah, I doubt it'll be any of those. The only ones that stand a chance are his original ideas. But I think he'll come out announcing something completely new that he's making. At least that's what I'm hoping for... and please don't be another war movie!
I know that a lot of you liked Dunkirk, but even if I liked it, I would have preferred him to switch up genres. I wasn't the biggest fan of Tarantino doing another western after Django and I wasn't the only one. That movie wasn't a big success (granted, for multiple reasons) and I think that Once Upon a Time will be a much bigger hit (again, for various other reasons, but still, a fresh setting is also important).
It was probably the best movie it could have been and didn't even break even. It's a clear sign general audiences aren't interested in this universe. No-one is paying for another. Maybe in another 35 years.