With his gold medal at the Olympics, I believe he's won every single title of note.  All the Slams (more singles than any player except Margaret Court), all the Masters, the Year End championships.  More weeks at number 1 than any other player.  All he's missing is the consecutive weeks at number 1, and he doesn't have enough career left over for him to get that.
I think he holds on another year or two, hoping to get slam #25, but I am not sure he gets it.