Stellar outfield, iffy infield, trouble brewing at catcher should Lieberthal be injured... very good rotation, another closer would be nice. Kudos on all the sp/rp's!
But you knew that already...
Do you have a bench? If not, your infield will hold you back. You might have to consider trading an of or sp for a bit more infield strength. That shouldn't be too difficult, though; you have a very solid team overall, but you should probably distribute the strengths a bit more evenly over the long run.