It is a weird notion that we can only have one player who is good enough for each position. As a top club you need a top SQUAD to be able to compete on 4 fronts and be in with a shout of winning one of the big trophies. For Chelsea Ramires is the odd man out, but still plays plenty, and behind him they also have Mikel. At Man City Fernando was bought as an alternative to Toure and Fernandinho, but he has played a lot of football this season.
Coquelin is already playing too many games the way I see it. Yes, he came in late, but he has played almost every game since he came into the team. Wenger really can't rotate him with Arteta unavailable because there is no one else.
The way I see it, Flamini is NOT good enough as a squad option. I am sorry, Biggus, but he just isn't. The drop off in quality is too high, and he is pretty much always the weakest link when he is on the pitch these days. We NEED another top class central mid who plays either instead of Coquelin, or alongside him in certain games. There are so many games in a season, players get injured, players are out of form, that too little game time is not even remotely a problem.
Schneiderlin would be a massive boost to our squad, fits the bill perfectly, and £20m - £25m should not stop us from getting him.