Did you notice you have Radke listed twice?
I think you have a solid all-around offense. Your infield is really balanced with Piazza, Sweeney, and Chavez for power and Castillo and Renteria for speed. Your outfield is pretty amazing, with Ordonez, Dunn, and Wilson! Kearns should do fine as long as he is healthy.
You may want to look into adding another starter for pitching depth. Oswalt is great, but he is your only top tier starter. Hopefully for you Beckett and Wolf will have nice seasons, but they are question marks. Radke is a nice guy to have at the end of the rotation, especially since he's on a great team. Lilly is another question mark, but again, plays on a good team. Looper and Contreras are nice guys to have on the bench. I think you definitely need another solid, top tier starter to lend some stability to your rotation.
Please comment on my roster
here.