[quote=@Nyxella]
Hi there, I have interest in what this might offer, all depending on one question: will this function as a sandbox with plots primarily driven by players or will there be a central story?
[/quote]

My thought is that I will present the basics of the world and the characters' situation, after which writers will create their own storylines, as you said, "sandbox" like. Of course, all storylines need to fit the narrative presented: the prehistoric world of 10,000 BCE. No one's going to meet aliens or discover a box full of laser rifles or whatever. And I would prefer (but would not demand) that writers at least PM me with a basic direction for their players, so that I will be able to see if writers/characters are going to come into conflict with one another.

I want everyone to feel free to have their characters do what they wish, while also respecting other writers.

Does that help at all?