Red Dead Redemption 2: 10 Single Player Expansions We'd LOVE To See
4. Adult Jack
Jack Marston's story is arguably the most tragic of them all. He was raised in a gang, just like his father and his uncle Arthur. It's all he knew. Arthur sacrificed his life to give John - and more importantly, Jack - a shot at a better life. John did the same at the end of Red Dead Redemption, and what did Jack do with that gift? He squandered it on revenge.
A lot of people have suggested that the third game (or a DLC) should follow Jack as a John Dillinger-esque outlaw in 1920s Chicago. To explore such a thing in a DLC would require Rockstar creating a new map, which they wouldn't do. Plus, that wouldn't be much of a Western. There IS some merit to that idea, though. It seems like a rich story in the making.
What if we see Jack return to Saint Denis and enter a power struggle with Guido Martelli? It's been fifteen years since he set foot in Angelo Bronte's mansion. What if he goes back to carve out a piece of the pie for himself? That would allow us to play as an adult Jack, but it wouldn't sacrifice the series's Western motif.