This gives you a small stat boost and access certain themed events, often improving your skills in that area. One of the ways Way of Life achieves this is by allowing your ruler to pick a ‘focus’. How much you enjoy this side of the game will determine whether you pick up this DLC or not, but I absolutely adore them, which is why I’ve rated this so highly.
Way of Life is focused on the role playing aspect of Crusader Kings, specifically ‘events’, those little ‘choose your own adventure’ pop ups that appear as you play informing you that your ruler has taken up falconry, insulted a priest, or slept with their sister (that last one comes up a lot).