I mentioned in a post earlier about cleverley and Ando. I would have loved to have seen how we would have progressed if those two stayed fit. Some of the football in the beginning of the season was top class. But as you point out: the injuries came.
For me, it has been the lack of energy in the midfield, and an inability to be able to cope with teams who play a high pressing game. The games against Bilbao and Wigan spring to mind. We couldn't cope with the energy of their midfielders', which was compounded by the fact that they both played with three in the middle. In times past United have had a good balance in the midfield: Roy Keane, Paul Ince, Nicky but, Owen Hargreaves and Darren Fletcher all offered energy and steel to the midfield. It goes to show how much we have missed Fletch this season. His energy, determination and 'passion' has got us through a lot of big crunch games.
I think it is a must that we sign a midfielder with energy and determination; preferably with good technical attributes. Javi Martinez springs to mind. If we can get a player of that ilk, to complement the emerging young talent, I feel we will be far more effective as a team.