Kalac is good, they only lost against Arsenal last year because he let his guard down, thinking it would go into extra time and that caused his hesitation and the goal. Milan need to rebuild, and in order to do that, they gotta get rid of Ancelotti. He's too stuck-up to his morals, and all he ever wants is attacking players (those two defensive players (Zambrotta, Flamini) he bought this summer don't count).
Ronaldinho isn't gonna do anything for them, he's a filler for a position that isn't needed (Ambrosini was a supporting cast because he had the stamina to chase after attackers and play the ball forward, Ronaldinho is like Kaka', and when they're paired together, let's use WC 2006 as an example, one overlaps the other and they don't end up both playing well).
Milan's been on the downfall ever since the departure of Shevchenko. They lack a player who's consistent up front (Inzaghi is kinda old, Pato only scored in his first few games, Oliveira was a complete waste of money, Boriello is now injured), they NEED sheva. Plus, Kaka'+Sheva=DOOM.