I think you should stay put. You have so many young OFs that you should hang on to them and make sure you get the ones who stick. Your pitching is deep enough to not need Slowey.
Reimold is worth more than Slowey, especially since we don't know how Slowey will start the year after his wrist surgery. Since I also think Cordero is better than Soriano, I would definitely not do this deal.
Lower-tier closers are worthless to trade for in keeper leagues, you can always find cheap saves in free agency. Oswalt is good, but he's on the downside of his career. Austin Jackson is a decent young guy, I'm interested in seeing if he can develop any power, he has the chance to, but its not a guarantee. If you are going to trade Reimold, you would need to get better, and younger, player in return. Who else does he have on his team?