Players that combined great technique with athletic ability and power were always scarce and after our exploits in the unbeaten season started costing even more. I remember Wenger was desperate for Essien and even wanted Drogba. Ultimately we couldn't match Chelsea.
While I despise Fabregas now, Barca didn't play football like they did under Guardiola when the reigns of our midfield were handed to Cesc. To be fair we played some top class attacking football with him in midfield and were on course for a 100 goals when Cesc and Van Persie were fit together.
Wenger didn't completely shun power and pace either. Adebayor, Song, Diaby, Walcott were bought in for one aspect or another. In my opinion there in lay Wenger's biggest fault. He didn't commit to one philosophy. He tried to stitch together a team of technical players with players that brought in physical strength and he failed. If anything, he needed to add more technique to play the football he tried to play, even though football in England is so different.