I don't really see the controls being hard at all. 90% of the time, all you need are these:
WASD - Movement
G - Throw grenade
R - Reload
Mouse wheel and button - Scroll through action menu and select action
X/Z - Crouch/prone
Left/right click - Fire/Aim Down Sight
Q/E - Lean left/right
I - Inventory
N - Night Vision
Alt - Free look (Turning your character's head while not turning the body, useful in vehicles)
For the stance modifier, it's just Left CTRL + WASD.
It's almost the same as usual FPS games but with a couple of more keys. Almost all of the keys above are reach-able by your left hand.