I'll love to see him get a rematch with Margarito but who knows if that's ever going to happen. Cotto staying at 154 though would be a bad idea imo since he looks really small at the weight, moving back down to 147 would be best for him.
I think it will be Chavez Jr next...if he gets past Duddy. I think Cotto v Williams would be a good bout...not sure it will happen though.
I think he fights Chavez Jr next. Would be a solid fight for the Mexican/Rican rivalry. An undefeated Mexican who is the son of Mexico's boxing jewel against PR's current best fighter. Personally I want him to fight Williams.
Give Cotto a couple easy but respectable wins @ 154 over the likes of Chavez jr, Cintron and Angulo, then his confidence will be enough to bring back the Cotto of old but more better.