I like what you have but I really want to get Cashner into the rotation so we an see what we have in him. At times he looked dominant last year. Also I like Koyie Hill, he is a leader in the locker room and is good defensively but like you pointed out he is absolutely useless with the bat. We will see how they have Castillo rated, that is definitely an option to have him over Koyie as the backup to Geo.
Only thing I don't like is DeWitt batting 2nd and ARAM batting 3rd. I think Aramis is much more comfortable batting 4th, and he strikes out/hits into too many double plays to be a 3 hitter. Byrd would also be a good option batting 3rd besides Colvin, I just like ARAM in the 4 spot and Pena in the 5 spot a lot.
What are your thoughts on the pen?