I think Senderos will surprise many people positively in serieA. In other words it annoys me that you've gotten him.
He will make a gaffe now and then, but in the main he will be solid, strong in the air, no nonsense, not fast but not slow and positionally aware.
Clearly he is not a superstar signing, but I would rather play him than Kaladze.
On something else, one can definitely debate whether you've spent your money wisely (considering that salaries are an ever more important compartment), but one can hardly say you lost anyone important apart from the loss of ageing players deterioating, and the haul before 2008/2009 - disregarding youngsters - could be said to be:
----------------Abbiati
Zambrotta Senderos---X-------------X
----------------------Flamini
------------Ronaldinho
---------Boriello---------Sheva
Thats seven quality players no matter how you look at it, and whereas the appropriation of funds is debatable for the long term, you cannot point to many - if any - teams among the bigs that strenghtened more.