I just think of any hero in the Marvel U, the hero right now that embodies modern America, would be Luke Cage. Think about it. He's a young father who looks out for his neighborhood who'd been given a second chance at life after a jail sentence. He's tough, smart and is a high level street fighter. He'll have the chance to prove his leadership since becoming leader of the New Avengers.
I may be wrong, but if I was in charge, I'd happily make Luke the new Cap. He fits the mold, imo.
Luke's powers are the product of an offshoot of the super soldier serum. He being Captain America makes sense.