Thanks for your help on mine.
I wouldn't dump any of the hitters on your roster for the hitters you listed as available. If you need HR and RBI (hard to believe, looking at your lineup), you might be able to deal Alex Gordon and Dustin Pedroia for an Adam Dunn-plus or a Mark Trumbo-plus. Something like that, maybe.
The only pitcher on your available list that I might pursue would be Doug Fister, but I'm not extremely optimistic that he's going to regain the value he had last year. He WAS amazing in the second half, though. Still, I don't think I'd drop any of your pitchers to get him.
As for pitchers to target to lower your ERA and WHIP, make a run at Jordan Zimmermann. He's an ERA and WHIP machine, and a bit underrated. His owner might be frustrated by the lack of wins -- he tends to get low run support, and rarely goes more than 6-7 innings -- and strikeouts, but you can feel confident plugging him in as a stabilizer in the categories you mentioned.