I've decided I will stay with a 4-3-3 like i've used since season 3, I'm in my 16th season now. I've had very good success with a 4-3-3 formation, so i will continue with it. I realised the problem was i was using the same players too often over the last 3 seasons which was making their form drop, thus affecting my results, so i will rotate my squad more in future.