Another feature that was expanded upon in Grand Theft Auto V, customisation needs to be heavily upgraded in Red Dead Redemption 2.
The original Red Dead only really allowed pre-set outfit changes that had to be unlocked through special actions. Whilst these outfits were all pretty fitting for the game, the sequel needs to allow for deeper and more personal customisation.
Hats, trousers, waistcoats, suits, masks and boots should all be changeable to some degree, with players getting regular access to their own personal wardrobe. Do you want a character in a suit and bowler hat? How about a duster and a stetson? This level of customisation is essential - and somewhat expected in open-world games today - for Red Dead Redemption 2, not to mention Red Dead Online.
The original RDR's online component only allowed you to choose from a range of archetypes and set characters. Why not introduce the ability to have a brand new cowboy join the gang? This character could even appear in single-player as a member of the gang.