I think the best trade is a Suarez/Kelly or Suarez/Gallen combo deal. IMO, that would make it worth it for Jed to give up Caissie+, which is where that convo probably begins.
Just spitballing - maybe Owen Caissie, Ben Brown, Ballesteros and a low level guy with potential for Suarez and Gallen? I'd bet the D Backs want guys that are near MLB ready, since they have a pretty good roster in place. Just a bad year for them in a loaded division.