The point you bring up about the money is a very good one, and, if they decided to retain Abreu (either by picking up his option or resigning him), they're going to want to save money.
I just feel that the other guys fit better. The one guy that I really wanted was Ichiro, but that's no longer possible. The Yankees really don't have a ton of right handed hitters that play every day, which makes them slightly weaker against lefties.
Torii Hunter vs. LHP: 118 ABs, 10 HRs, .363 OBP, .644 SLG
Aaron Rowand vs. LHP: 133 ABs, 5 HRs, .395 OBP, .564 SLG
Melky Cabrera vs. LHP: 112 ABs, 1 HR, .344 OBP, .375 SLG
I understand that it's a small sample size, but it's pretty telling. Clearly Yankees Stadium is a lefties park, so it's important to have some really good left handed hitters, but there needs to be some balance.
In terms of Zambrano, I'm not saying he's not a great pitcher, and I'm not saying that he's not better than anyone the Yankees will have, but where are you going to put.
2007 Yankees Rotation (barring injuries):
Chien Mien Wang - a definite
Phil Hughes - a definite
Andy Pettitte - assuming his option will be picked up
Mike Mussina - no other place to put him, unless you can trade him, which is unlikely
Joba Chamberlain - not a lot of choices here...unless you keep him as a reliever next year, but I don't want the Yankees to have the mindset with him that the Red Sox do with Papelbon
I would love Zambrano, but the year to sign a starting pitcher might be next offseason, when Pettitte and Mussina come off the books. On top of that, I think there's a good chance that Zambrano resigns.