It's only really at CB where we lack depth though. Arteta and Flamini are past it but that's still two decent options for one position. And I'm pretty sure back then was the days of playing any old joker at the back with Almunia in goal, so it's not like so it's not like we're worse of there now than we were.
I guess my general point is that if the team is stronger but we're not doing better that's pretty damning on the management of the club. We just don't do well against other sides that have similar, or in some cases marginally worse, squads than we do. Even looking beyond the drubbings against tittle challenging sides, take Wenger's record against Martinez's Everton. They've played two games at Godison, and two at the Emirates, yet despite Arsenal being much richer, and having stronger squads, it's 2 draws, and 1 win each, with an aggregate score of 7-7. In other words, their performances against each other have been completely equal. Arsenal are so rigid in their tactical approach, that you don't even need to have equal or better players to excel against them if you properly know what you're doing.
I've said before that I probably don't think Wenger is the best man for the job anymore. The issue is I don't know who is that would be available, and while the possibility of a new manager taking us to 10th is stupid, it'd feel **** letting Wenger go if it didn't lead to a significant improvement.