Who says the other targets are available, interested or fair value? There's probably loads of available players who aren't good enough, as well as a few good enough ones who aren't interested or don't represent good spending.
How many strikers have moved this window that you'd have been happy with (excluding those who turned you down)?
We have 1 good forward who doesn't score many goals, 1 championship level striker who doesn't score and offers nothing else and another who will likely never play again. I cannot believe Arsenal cannot do anything to improve that situation in the window.
EDIT
And as for central midfielders we have 2 premier league quality of which one is completely brain-dead. Again, can be and should be improved.