At first look, I was thinking absolutely take the deal. The more I "over-analyze" it though, I'm not as certain.
I like Cabrera a lot and I'm one of the few that hasn't completely bought into Starlin. Cabrera is only 25 and is a great keeper himself. I think he and Castro will both produce solid BA, R and SB with "limited" power numbers. I definitely give Castro the "upside" advantage but just how much better, I don't know.
Ethier vs McCutchen is interesting. Ethier's in his prime and proving to be very good. He'll have a superior BA, HR and RBI. McCutchen's going to be better in the R and SB but how much behind in the other numbers by the time he reaches Ethier's ripe age of 29? I guess I'm giving the upside advantage here to McCutchen, for sure.
Hudson? love the K-potential here. I think he's going to be a really good SP. But, is he going to be a future star the way just about everyone expects McCutchen and Castro to become? Prolly not. I view Hudson as the next Jonathan Sanchez.
In the end...
I'm sticking with the initial feeling...DO IT. McCutchen over Ethier based on age and upside. Castro over Hudson based on position value. Stud SS's are much harder to find than solid high-K SP's. Now, again, I like Cabrera a lot and I would certainly "dangle" Castro as soon as I get him. There is someone in your league that will fall all over themselves to get Castro and you could really hit a homerun. Or, if you think he's the next Jose Reyes, just hold onto him and enjoy. You'd have a heck of a 1-2 punch at SS.