Since I changed my formation/tacits from 4-5-1 V to 4-1-2N-1-2 (4-4-2 diamond), I´ve never lost a game (praise the lord) .... Also, I never change my formation/tactics during a game, just sub some players out/in. I think "balance" is a key to sucess.
Actually, I got only 12 players that I use in important matches, and 3 formations, narrow diamond, 4-5-1 V and 3-5-2 V. My AMC is also an AMR, so when I go V-Style, he just moves to the right flank and I swap an AML in for either my weaker striker or my weakest DC.
Bermuda Triangle, started 26.2.2013
standings/trophies (9 seasons, 7 promotions):
League winner: 4
Champions league winner: 2
Cup winner: 2