There should be different ways on how we can hold a rifle or lightsaber, so instead we can hold a lightsaber such as Luke where he holds it in the center or Obi - Wan with his "two - fingered stance"
Edit - From Romothian's response, they should change depending on which form (if it's a lightsaber) it is. So in Soresu we have Obi - wan's stance, as we know he was an expert in it, or if we are in Ataru, Ahsoka's or Starkiller's stance.