I play on world class with the sliders adjusted a little bit and I'm 8 points clear at the top of the league with Villa, may have to go up to legendary.
The trick for me is use your midfielders or even forwards to do all the tackling until the opposition get to the edge of your box and then use your defenders.
I play 4-1-2-1-2 formation with 1 CDM, 2 box to box midfielders, 1 CAM and 2 strikers. Oddly enough but since I started using "ultra attacking" tactic, I seem to concede less ?
Having a really fun career mode with villa, Sold Gabby for £20m and Benteke for £28m, brought a load of players and then sold Serge Aurier who Man City then brought off me for £46.5m! Most I've spent on a player is £14m on Perreyra from Udinese but mainly been around £5-£10m mark with a few £2m bargains
My team:
Guzan
Montoya
Ogbonna
Schaar
Gaya
Malanda (RIP)
Delph
Perreya
Morralez
Ings
Babacar
Bench:
Okore
D Suarez
Musa
Dybala
Vilhenna
Poulsen
Sanchez
Joel Campell
Wellington Nem