If Mayweather's out of the picture, Oscar should fight Trinidad. That fight would sell massive PPVs! Plus, Oscar isn't exactly at the "make an impact on the division" stage of his career - so why not go out with an entertaining bout rather than a dangerous fight with one of the current 147-154 contenders? I thought Trinidad looked good vs. Jones (despite the outcome), and I think he'd look even better against Oscar. Those two both have enough in the tank for one last go-around - and I'm still not sure who'd win.

Oscar-Trinidad: tons of cash, plus a chance to leave on a high note.
Oscar-Cotto/Margarito: still a lot of cash, but probably not as much, plus a much more dangerous fight.
Oscar/Mosley: It would probably sell pretty well, but we've already seen it twice
Oscar-Mora/Collazo/etc. : Weakest option, financially and from an entertainment point of view. But ODLH has had an awesome career, so he should do whatever he wants to to end it.