I use 4 5 1 v alot and I was using defensive mentality won all my cup, cl and league matches then lost my top of the table clash 1-0 even though all my players are world class and all of his were scouts.....seriously dont understand how the game engine works but anyway it was a big wake up call notice he had 3 times as many shots than me but I had more possession obviously cause I was defensive and I was playing a possession base game. So I changed to Attacking, Own Half, Down both flanks, Zonal, Mixed Passing, counter attack on. I noticed you gotta have really good wingers (AML,AMR,DL,DR) otherwise you get punished as I put red arrows on them and the Striker. Put blue arrows on DMC and the 2 DCs leave the MCs unless opponents have really good MCs. I haven't leaked a goal since that lost however I've noticed I've been giving away a lot more cards which makes sense with 5 red arrows and attacking mentality its effective though at least for me.