I really think that the fall damage height should be boosted just a tinsey bit. I hate jumping out of my vehicle to find that I just lost 20 points of HP. Anyways, that's my only complaint, keep up the good* work.
I've had this, too. I'll jump from a five foot high hill and hit the ground and take damage. I'll jump out of a speeder moving at 5 km/h and take damage, or even die. So I, too, agree with the OP.
"One of the bitches actually gave birth while she was attacking, and her puppies joined in on the carnage." --the awesomeness that is Boatmurdered.
You should increase the height where you don't take damage(Taking stamina 'damage' would be cool and more realistic, if possible). But increase the damage taken when you fall from above the damage height.