All of the speculation about Contreras to the Rays, how about Caratini to the Rays for Margot? Saves them a few bucks while improving their catching and gets the Cubs a young CF. Sign Grossman for depth in the OF and Happ can play LF, 3B, or 2B as needed depending on future transactions (i.e. Bryant). I like Margot for Caratini a lot if Willson doesn't get moved. Though I don't see it making sense to not move Willson, unless maybe you move Darvish or Hendricks. Which I guess brings us to:
I see the merits of moving Darvish. Always better to move pitching sooner rather than later, and Darvish is incredibly valuable right now. That said, like Brett alludes to at the end there, if you're moving Darvish you ought to just mostly blow it all up. It might make sense to trade Darvish (for a huge haul) if you could be sure the offense would rebound, but that's far from a sure thing. You would need to get a good young SP to put in the rotation right away, a good young position player that steps into the lineup, and some very good prospects.