I take a very similar approach, Millie. I have just ONE tactic named '4-4-2 basic' and all the team sliders are left at their default. The individual instructions that I have implemented are the ones that I know that I will probably be keeping the same all throughout.
I begin the game, check out the opposition formation and any potential weaknesses (such as a 14 year old female right back

), and then I go from there. I would safely say that I NEVER play the exact same instructions twice in a season—either from the beginning or during the game. I am of the opinion that this is true for every football match in real life in the Premiership. Yes teams will play the same formation, but there is always a different approach for every opponent. I am successful so I am happy with this approach. It seems to work (although who knows? That's for another thread), and it gives me the most satisfaction as a gamer that I am actually analysing the opposition and adapting my theories on the game to outsmart my opponent.