What do we want to happen in this game? Not just the big arc, although that's certainly important, but minor plot and character stuff as well.
Romance! Intrigue! Betrayal! Exploration! Mystery! Raising farm animals! There's an endless array of possible things to do with the story, and we should pick out a few to use here.
What do you like to see in a game?
For myself, I'm partial to a little romance, and a lot of character development. But that's just me.