In the examples velow you can see why some basic examples need to happen eventually. the chars look like from a decade ago w/o any form of facial expressions.
maybe start with blinking and later squinting when having heavy weather or when having dusky/dawny light.
maybe basic good mood (fit and healthy) expression, basic bad mood expression (wounded) or focused expression (aiming, shooting)
examples from the latest exp update:
https://dayz.com/assets/video/inventory.mp4
https://dayz.com/assets/video/drinking.mp4
https://dayz.com/assets/video/eating.mp4
https://dayz.com/assets/video/gestures.mp4
https://dayz.com/assets/video/blocks.mp4