While your ideas are good in theory, the chances of Cotts being the 5th starter next season are pretty good.
The way I see the rotation next season is this:
#1 - Buehrle
#2 - Loaiza
#3 - Garland
#4 - FA Signing (it won't be Ponson, more likely a Brian Anderson, Suppan type)
#5 - Neal Cotts, Jon Rauch, whoever impresses in ST.
I think a lot of fans are going to be disappointed when the Sox don't get all of these guys that are discussed everyday on these boards like Hawkins, Castillo, Ponson, etc. Personally, I don't see any of them coming our way. In our economic situation, we aren't going to be flexible to make any moves that will add 2 or 3 impact type players or pitchers. Don't get your hopes up.