Agreed.
We have two ways to go now. First is a classic 4-2-3-1:
------------RVP-----------
Di Maria – Mata – Januzaj
----Herrera---Carrick
The main flaw of this system is that both Herrera and Carrick are not suited to a midfield of two. Mata is best high up the pitch. We could play Rooney instead of Mata but from what I’ve seen from him for some time I don’t want him to come deeper.
Therefore, we should go with a proper 4-3-3:
-------------RvP----------
-Rooney-----------Januzaj----
----Di Maria----Herrera---
-----------Carrick---------
This will give us a lot of control in midfield, with players capable of defending and attacking (Carrick needs to stay deep though). This is the best we get from all of those players bar Rooney (we can also try Welbeck in that position). Another plus of this is that we can easily switch to 4-4-2.
Di Maria is a pretty good winger, but he is much, much more effective and useful for the team in midfield, and that’s where we should play him.
I think we are best off trying to use our huge squad depth to adjust the selection to the opponents. We just have so many great options right now that for every tactic and match up the best possible selection would differ.
Not many teams can line up so completely different, tailor made for the opponent like us. Kagawa is much better defensively as an AM than Mata and he's better as a pure counter-attacker as well. He was our second best winger defensively last year after Valencia and he is the one who stood out as the best suited against a high press against Bayern.
Rooney and Welbeck are good solid options as winger for a counter-attacking team as well, Welbeck displayed that as well in the CL before. Januzaj/Mata are by far the best options we have when we want to dominate the game and unlock a tight defense. But defensively both of them are poor and could cost us when we defend 95% of the game.
Defensive line-up against a high press where you need great possession keeping to handle the press.
------------------DDG----------
Rafael-----Jones-------Evans------Shaw
-----Di Maria-Fletcher-Herrera----------
---Mata-------------------------Kagawa--
-------------------RVP---------------------
Regular counter-attacking/defensive line up
Rafael-----Jones-------Rojo-------Shaw
-----Di Maria-Fletcher-Herrera----------
Welbeck----------RVP------------Rooney
Against teams we dominate and want to beat
Rafael-----Jones-------Evans------Shaw
-----------Fletcher----Herrera
---Januzaj-------Mata-------Di Maria----
-----------------Rooney-------------------
Not that these are the perfect examples of how it has to look, but I think it shows that we can put out a lot of different formations which would be the best for different match ups/situations.