Costner is like a figure charting the American journey
by intention or design hes sort of chartered the American journey/Americana throughout his film career more so than any other leading actor (like Clint).. The old West (Dances with Wolves etc), the gangsters era of the 30s (Untouchables),the JFK saga (JFK, 13Days), the 60s (Perfect World), baseball (Field of Dreams etc), the ultimate American superhero (MoS), Elvis (3000 Miles to Graceland), and even the potential future (Waterworld, Postman)..
and although he's never done a sequel (bar BvS) each movie is like a sequel or prequel unto each other charting the American dream..