Well, not so much Checkhov's Guns for Arc 1.
What I mean is that we probably should have the end-game and the mile stones that get us there at least roughed out - not to the point where we can't have new writers coming in, but enough that we now have a lay of the land in our heads and know what plot points we want to hit along the way. Some of those might need some set up; not so much as a 'Chekhov's Gun' or such, but just plain, ordinary plot development.
I already know that there's gonna be some developments that might jump out at us along the way, but even so... Well, you get the idea. :p
What I mean is that we probably should have the end-game and the mile stones that get us there at least roughed out - not to the point where we can't have new writers coming in, but enough that we now have a lay of the land in our heads and know what plot points we want to hit along the way. Some of those might need some set up; not so much as a 'Chekhov's Gun' or such, but just plain, ordinary plot development.
I already know that there's gonna be some developments that might jump out at us along the way, but even so... Well, you get the idea. :p