There is not such a thing as best formation or tactic, all can work good I assume. My only advice is to use just one striker and focus on offensive wingers as they seems to be overpower at the moment so AML / AMR ?

Currently playing a formation I never liked it but I said to try it and seems to work or at least seems to work for me and goes very well in defense as well.

3 (DC) - DML / DMR - 2 (MC) - AML / AMR - ST

Just try to use your best 11 players and check for the transfer market if you can buy something else to improve it.