A change to the Shape's height (ie size down Myers)
Myers in-game seems rather large in stature, compared to how he is usually in the films (that is, if we exclude Rob Zombie's adaptations).
This alone doesn't seem too bad, but of we were to have him scaled down appropriately, it could give him a good buff for him in regards to gameplay, mostly since he'd have an easier time trying to mindgame more loops, where the Survivors can see him with his stall stature at the moment.
I do realize that this would mean tweaking his animations, and maybe in some regards reworking some of it, but I personally feel it could help him be a bit better in the higher rank, and makes him look more appropriate in regards to his Movie personality and looks (since I assume the look we have now is taken from the first movie, where he conveniently is also not this tall as we have him at the moment).