Overall, I think your team is fairly well balanced... not only between hitting and pitching, but also between reliable guys (Lee, Halladay, Pettite, Crawford) and guys with alot of upside (D. Cabrera, Barmes, Morneau).
I would hold onto Morneau. He is still very young. He had a weird off-season the year before last... he had appendicitis and mono or something weird like that. I think he will come back to be a 30+ homerun guy.
Overall, a very good team.