Ok, I don't feel like rewriting the whole message. Basically, in short:
If it were up to Wenger, I think Hleb, Flamini, and maybe even Gilberto would be in this seasons roster and most likely starting XI. These players decided to leave, thus furthening the process of transitioning. Last year can be considered a pretty unlucky season, but I don't think you can say finishing 4 points behind the leader is an unsuccesful season. Just think if Wenger had those players and a chance to build up on that. Instead he had to step back and rebuild over.
Secondly, the replacements I believe are a result of finances. Nasri was the replacement for Hleb, and that was all the power the club could muster for transfer. Arsene Wenger had to make a choice and he chose offense. I'm sure Arsene would love to have a top class holding midfield on the squad. Who wouldn't. But I believe he simply couldn't afford the quality of player he wanted for the budget, so he chose to trust in his students that he had been raising for years. Maybe they didn't deliver, and maybe they weren't as good as he thought, but what other choice did he have.
About the experience. Players on the squad who I would count as used to the EPL and a possible source of leadership on the field for other players.
Almunia, Fabregas, Toure, Gallas, Rosicky, Van Persie, Eboue, Adebayor. Now these are all players who ideally would be in XI or at least forcing their way in. I don't think it would be fair to call that deprived of experienced players. But think of it like this as well. Ideally Hleb, Flamini, and Eduardo would be on that list this season as well. But they're not, and when Fabregas and Rosicky and Adebayor and Toure and etc get injured out of that list it really becomes a problem, but you cant say much about injuries can you?
OK that's not really in short. I wrote much more than I wanted to, and I dont want to elaborate more. I honestly don't see anything positive coming from a coach change for Arsenal right now.