There is no point just pointing the finger at Floyd. Him and Manny dont want to fight each other. If you dont believe this then you are just a fanboy of one of them. This is one of the reasons why boxing as a sport is such a joke. What kind of sport would tennis be if Nadal and Djokovic were to afraid to play each other dew to fear of losing there status. It would lose loads of fans.
On the basis of who he can fight other than Cotto it depends what happens next. If Manny loses to Bradley then I would give him a shot. If Canelo beats Mosley then he could have a shot even though he is still a little green. I would rather see Canelo fight Cotto when Floyd beats him. It would be a good test to see if he has a chance against Floyd.
I would say Khan if he beats Peterson and then beats bradley. He needs these two under his belt to prepare him for Floyd. He could probably match floyd for speed and endurance but technical skill one again Floyd puts him as everyone to shame.
And then the most credible challenger for him to fight at the mo would be Martinez. He could box Martinezes head off all night but Martinez always goes for the ko punch in every shot he only needs one to land right and make sure he finishes the job in the same round.