I agree with you. And I still have faith that things like luck and this "system help" aren't the major factor. If that's the case, I'd be really disappointed with the game.
I have been playing football managing games from Elifoot98 to FM 2016, until I decided to play Top11. I'm just addicted to football .
The first games of this kind were about pure luck, until "Championship Manager 4" made some kind of awesome simulations. And then Tactics were the most important from Championship Manager until Football Manager 2016.
So, based on my "experience", I built an excel spreadsheet to help me calculating probabilities of winning matches depending on formations and instructions. Ofcourse, I don't know the maths behind the game simulation, I just made some sort of assumptions that I think it's right for the game. Take a look below:
Seeing things like those unbeaten 3N-1-2-3W-1 and 3W-4-1-2 makes me think I just wasted my time and my brain developing it