I think the squad has enough experience at this point. Fabregas, Van Persie, Rosicky, Arshavin all bring good experience to the side. A top defensive midfielder adds some more. Their CBs have decent experience and Almunia is experienced.
On the goals front, Arsenal scored 80+ goals last year. They create a lot of chances and get a good amount of goals from midfield. Not concerned about their need for a top front man. They can get enough creative play from quick creative wide players like Arshavin and Walcott + a top playmaker like Fabregas to make up for their strikers.
The keeper is an issue but with a top defensive midfielder I think Arsenal can cut off a lot of those areas where they've conceded goals + goal-scoring chances + failed to regain possession over the past few seasons. Give the side greater balance on the pitch. I reckon they can live with Almunia.
Van Persie and Rosicky are both very injury prone. And I wouldn't expect the same season from Fabregas as last year as I'n not sure how motivated he is after Arsenal twisted his arm this summer.
The CB's are not anywhere near the level of Terry, Vidic, Ferdinand... Vermaelen is o.k but nothing special, Gallas is gone and Koscielny is decent but not a top player by any count. That's (+ keeper) why United conceded only 28 while Arsenal 41.
And the luck of top striker was very visible when Van Persie was out last season. Arshavin ans Cesc created plenty but you still need a finisher of Drogba, Torres, Rooney quality or at least something similar. While Arsenal scored 80+, Chelsea scored 100+ .
Goals scored -- Chelsea were the first team ever in the Premiership to score 100 goals in the season. The number of goals scored by the Champion in the previous eight years are 68, 80, 83, 72, 72, 73, 74 and 79. Arsenal score enough goals to win the title. Both Van Persie and Rosicky played only 14 games apiece last season and even with those two players injured for the vast majority of last season Arsenal still had a hugely effective and prolific attack.
Fabregas -- I wouldn't be concerned about Fabregas. He is not the type of player to give sub-par effort. He has a huge amount of respect and affection for Arsenal FC and his manager Arsene Wenger. Fabregas isn't the type to create problems and he isn't the type to give less than his full effort in training and/or out on the pitch. He'll be Arsenal's leader again next season.
Goals Conceded -- A huge portion of the goals Arsenal have conceded over the past couple of years have been due to the lack of an adequate defensive midfielder.
If you go back over and watch all of their goals that they've conceded you'll see a large number of goals which could have been stopped by a top class defensive midfielder long before there was ever a shot attempt made on goal. Possessions where Arsenal's central midfielders weren't aggressive enough in the tackle to win back possession + a large number of possessions where the defensive midfielder was out of position (particularly for covering wing backs on forward runs) and unable to offer sufficient help as a result.
I reckon a top class defensive midfielder would cut Arsenal's conceded goals figure by 25%. That would put Arsenal right around 30 goals conceded for the year. Not a great number by any means ... but it is a number that gives them a legitimate shot at the title.
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In summary, I think that one position, defensive midfielder, filling that position with a top class player would give Arsenal a huge boost. It would balance their side and give their backline the protection it needs to have in order compete for a title.
Anyway, it's not going to happen. Wenger has shown no inclination for the third straight summer to fix this glaring hole on his squad (since Flamini left).
