Edwin Diaz is an okay throw in prospect (100-150 range). Kivlehan is a non-prospect. Austin Jackson is garbage. Rodney is old as s***, bad this season and a free agent at the end of the year. Hultzen has major injury problems. Tyler O'Neill and Gareth Morgan don't carry much value right now more than a throw in, if that. Miller would be nice. But that's awful return for Bautista + Reyes + Cecil + Pillar + Navarro.
Correa has the potential to be the best shortstop in the game, under team control for 6 years (and dirt cheap for 3). The Astros aren't trading him right now.