Honestly, we may get more for Oliver hanging on to him and trading him in late August. Some contender is bound to be pretty desperate by then, and non contenders are unlikely to claim him.
Kennedy has a career xfip of 4.1 and is a fly ball pitcher. I'm not convinced he'd be much of an improvement for us. I'd be okay with it if we flipped him, but otherwise I don't see much point.
I don't really want Kennedy unless we were to flip him. However, that haul seems criminally light for the Dbacks. I will say that Stites is putting up incredibly impressive numbers in the minors though for someone who seems to not be much of a prospect.
I seem to recall reports of A-Rod possibly using steroids since highschool. If MLB believes that he's been cheating repeatedly for years, I could understand them wanting to ban him for life.
JJ would do nothing for them since it appears they have given up on the season. I would think it would cost something more along the lines of Gose + (Minor league pitcher not named Sanchez) + Izzy.
I think Peavy is a bit overrated by people right now (wouldn't have minded us getting him though), but I don't think trading Iglesias will bite Boston at all.
Teams would know about anything wrong with the players from the physicals before any trade was agreed to anyhow. The information coming out to us fans is not an issue that should affect trades in any way.