Defensive wall is meant to help only in Free Kicks...Just pray to Top11 gods that all the long range shots of your opponent gets blocked otherwise your are FUC*ED......
I play 3 Attacking Mid-Fielders and I know how devastating they can be......And the icing on the cake is that you have no DL/DR...LoL...
If you no DL/DR then do try playing ML/MR...