Lucas Matthysse is coming off a big victory over Ruslan Provodnikov this past April. This has given him many options. Golden Boy would like a fight with Pacquiao or Mayweather, Arum interested in Brandon Rios, Provodnikov wants a rematch (so do the fans) and Matthysse would like a rematch against Gracia. Viktor "The Iceman" Postol from Kiev, Ukraine is also an option.
Team Matthysse would like a homecoming fight in Argentina. Not sure if the fighters mentioned would be willing to fight in Argentina but this is the plan at the moment. Unless of course Danny Gracia, is willing to rematch. As far as Matthysse getting a shot @ Pacquiao or Mayweather, I would say that is VERY unlikely.