[Designincase]

The problem with side eye is the expression is always looking to the side. With eyes looking straight ahead, you can always turn the head in the direction of the action. If the action is to the left then you turn the head to the left. To the right - the right. If it's above/below, you tilt the head up/down.

With side eye, the character is always looking to the left no matter which they the head is tilted. It's incredibly limiting.

A shouting head is limiting in establishing mood but it can still look in any direction.

Try it yourself.

Record yourself looking to the side. Now maintaining that, try to look at other angles.

Then do it looking straight ahead.