We've lost a lot and I feel we have not improved. Drogba , Kalou and Malouda are probably our biggest losses.
Think about our ties against Barcelona and Bayern.
Drogba was essential in the Barcelona game and did create space for the wingers against Bayern where he took up the attention of their CB's (Kalou actually had a shot on target that Neuer saved). For all their faults, Kalou and Malouda we defensively responsible wingers who would track back to deal with attacks on the flank , something which none of our current wingers (Mata, Marin, Hazard) but Ramires have. They were essential in taking care of Bayern at the flanks.
We will probably have to face one of Barcelona , Real Madrid or Bayern again very soon.
When we faced Barcelona injuries to their back line (Pique, Puyol just recovering from injury, Abidal) and their front (David Villa, who would have provided some kind of width to Barca's attack and finished off the chances that Barca squandered and Pique, who can act as a sort of target man when teams park the bus) weakened them greatly. Could Chelsea beat a full strength Barca? What could we do without our Target man Drogba up front? How do we park the bus with wingers that can't defend?