Hi Darcy! Wow, I love all of these ideas, this is really good stuff. I love how it's both kinda meta-literal but also has such a great message.
You can definitely submit as many games as you like! It's an awesome goal and a few people are aiming for that, so go for it!
PbtA has a lot of great world building aspects, sometimes it can be as straight forward as providing questions to the table. But world-building + GM-less makes me think that maybe you can take a look at the Belonging Outside Belonging system? It's token driven (rather than dice), but you can at least see how the system asks people to build a world (draw a map, pick some elements) and how it makes things GM-less (it uses setting elements that can be passed around the table)
You can learn about Belonging Outside Belonging by reading DREAM ASKEW DREAM APART, the RPG that created the system. A good way to look at free resources about it is checking out the game jam that ran earlier this year! https://itch.io/jam/belonging-outside-belonging-jam
Those are my initial ideas, let me know if I can provide anything more. We can also see what other people in the community have to say!