I just dropped Piniero myself, but it was a choice between dropping him, Mulder, or Hudson.
I decided to go with experience.
I also have Dye on my team, and I like him more than any of the guys you listed above. He seems to be heating up, and he's got the history to do better.
Cruz is definitely an interesting option, though. If he really is heating up (he hit 2 HR yesterday), I'd consider picking him up.
Looking forward to back to back championships in 2011!