To me, they're pretty important. Actually my midfielders score quite a lot of goals. I haven't tried to change them lately, as the current v2 tactic still works wonders to me. I'm just enjoying the game at the moment, as I don't have much time to play.
If you try it, please let me know how it works
At the moment I'm playing with Fulham. I'm in my second season, currently in the PL after getting promoted from the championship. I'm second in the PL atm, United is first (They're undefeated after 27 games, they're unstoppable). I've only lost one game so far this season, and that was against United away (1-0 defeat).
My team looks like this:
Koval, Joe Gomez, Sviatchenko, Balanta, Flanagan, Amartey, Lasse Vigen Christensen, Ruiz, Patrick Roberts (Just sold Andrija Zivkovic), Sisto, Woodrow.
Sisto (11 goals) and Woodrow (18 goals) are my star players.
If I'm leading with 15-20 minutes left, I often substitute Ruiz (CM, Auto) for a more defensive-orientated player, and change his role to defensive + I change the mentality to control.. If I'm at home, with a lot of ball poss, I might even change the tempo to slower, shorter passes etc, to waste more time.
Roberts the inside forward I'm guessing?