From a historical perspective, the fight I'd like to see Floyd Mayweather Jr. take on next is against Sergio Martinez for the middleweight championship of the world. But unfortunately, like many other fights, because Martinez has a steady relationship with HBO (for the time being), that isn't realistic.
That said, given how Mayweather looked this past weekend and the current physical decline of “Maravilla,” I would favor “Money” to win that fight if it were to come to fruition.
But you know what might still be the most lucrative fight to be made in boxing? Mayweather-Manny Pacquiao. Yes, even now in 2013, believe it or not. My latest contribution to SportsOnEarth.com talks about it: sportsonearth.com/article/60868136/
According to this article in Forbes, (Floyd - $80 Million For Fight By Kurt Badenhausen, Forbes)
Mayweather could earn as much as $80 million for the Alvarez fight. But to get to that stratosphere, again, he will need to hit certain pay-per-view benchmarks, meaning facing certain guys who are not just more popular than the likes of Guerrero but perhaps bigger threats. Do Danny Garcia, Amir Khan, Devon Alexander, et al, bring that type of appeal?