Eh, at that point you might as well just do it all in your own head. Because yeah, the backstory is negligible at best. It doesn't really matter because there are things you can do that doesn't really fit into any prefab thing unless they just straight up have a text editor you can type in before you start your game.
Like, will there be a prefab backstory in any game that can explain me running around killing people solely by punching them? Probably not. Unless the prefab thing is that before the war I was a disciple of School of Hokuto Shinken, and after the war I am the last practitioner spreading my teachings.
Which would be pretty awesome, granted.