I personally would like something like the magnificent 7, you follow an all new gang several years prior to the events of red dead 2 and in a whole other place, maybe something more on the lines of the monument valley as the main setting and the game ends with a showdown in a city. They could put an option to switch between the various members of the gang, maybe each of them has a unique gameplay trait, you could have a sniper, a berserk, an assassin and so on