Since the red dead franchise is started with red dead revolver which was the first red dead games to be standalone and not related to red dead redemption , cus red dead redemption didn't existed yet until 2011, now the main question here is
Would it be really necessary for rockstar games to make another games of the franchise but not rather used "redemption" as third titles??, because take example on call of duty where the games has several different standalone titles but still within the same franchise like call of duty black ops 2 and etc,
so rockstar could make standalone red dead titles like that but s does it need necessary to just do standalone??, in rockstar games's standard??, because they make GTA franchise where the games has different standalone titles but take place in same place within same universe, (example: GTA 5 and GTA 4 take place in same universe)