Depends on your team and players. You need to develop your own, two or three tactics you'll use so you could become unpredictable and always in good position to win. New FM 18 and 19 are designed so you need to make changes to tactics and need to look your opponent tactics and exploit their weakness.
Your vision as manager is the best thing you can do for your tactics.
I am using 4-2-3-1 as home (attack), 4-1-2-2-1 (winger/ control) when play away, and 4-4-2 narrow when I need it.