i saw these topics had been discussed elsewhere but maybe we can discuss a way of gaining more realism while making cover more intuitive.
I would totally be fond of headshot doing more critical damage if not instant kill. If balance is the problem, maybe dev could:
make aiming circle way more large, and allow to spend willpower point to make it more accurate, so we cannot just headshot everything that moves, but that headshot still have an interest
as for cover, making sidestep mandatory everytime we shoot out of full cover, and making units hold against cover as i saw suggested in another topic would help reducing easy headshots while making it less frustrating to take full cover.