It's hard to know how to value Abreu, and all it takes is for one GM to like him, a lot. There is much to like, and even his defense seems to be pretty decent and can improve. His worst fault is how he hits LHPs. As of now, he is a very good strong side platoon RF'er and okay CF'er. He'd be a plus LF'er for most teams.
A simple swap of Abreu for a RHB might be a big help, and maybe we get a better player if we trade the 5 years of Abreu for 2-3 years from a RHB (SS, 2B, 1B, RF?)
We can us Ref in LF and O'Neill in RF vs LHPs, and Rafaela in CF vs RHPs, but then our middle IF looks shaky. Adding a RHB middle IF'er at the deadline could cure that, at a low cost.
I doubt we trade a top 6 prospect (Anthony, Mayer, Teel, Campbell, Bleis & Cespedes,) and I don't think we trade Zanetello, Perales, Fitts or Sandlin, either, unless we get back a good pitcher with 1.3+ years of team control. That still leaves some decent talent that can be traded for a 4/5 SPer, a RP'er or two and a RHB that plays SS (maybe 1B or 2B.)
I may be over valuing these guys, but we did get Schwarber for Aldo Ramirez, so maybe we can do something with these guys:
Abreu
Yorke
Meidroth
Lugo
Paulino
Castro
Jordan
Hickey
Mata (out of options and rehab almost done)
Additions like these guys might help:
Walter, Wikelman or Bastardo
Coffey or Sogard
Romero or McDonough
Guerrero or Hoppe
Brannon or Zeferjahn