Hitting: Solid at most positions, but I would consider the following
1. Getting rid of Choi and picking up Konerko, or Ben Broussard when he gets over his injury.
2. I would also get rid of Cruz, Jr. because of his past history of quick starts and bad finishes, and Floyd, because of the injury risk he is.
3. Durham, since he doesn't steal as much these days, and his avergae won't be that great either. I would suggest Brian Roberts or Junior Spivey.
Pitching: You are solid here too, but I would unload Affeldt as soon as possible. I've been reading that his fastball has lost a lot of velocity, and that his curveball isn't anywhere near as good as it used to be. If Eaton or Peavy are out there, pick one of them up. I look for both of them to post good numbers because of Petco.
This brings me to the trade you have proposed. I think it's a good one, since you'll be getting rid of 3 problem players and getting back solid players such as Dunn (who I think has turned the corner) and Miles (who will be an offensive sleeper at Coors).
I ask to please rate my team as well.