The main purpose of steep fall is to get you captured/enslaved/defeated or have your licences processed or any other bad force greet. 
Falling to ridiculous heights should still kill you IMO to discourage running down mountains. 

Steep Fall automatically applies perks 'DeathResist' and 'FallDamageReduction' when falling to (respectively):
A) Help you survive physical and magic attacks while ragdolled so that defeat/FG mods can have their way with you when you get back up. 
B) Help you survive reasonable falls.

Doing certain things while ragdolled can be buggy (esp other animations).

JSON SETTINGS:

fallheight = The difference in height you can change between checks. 
If your change is higher than this you'll fall. If it's lower then nothing will happen. 
Set this too high and you'll never fall. Set it too low and you'll fall all the time as if the ground was made of wet fish. 

crawlallowance = An extra allowance to the height you can change while crawling. 
Crawling will allow you to climb steeper slopes without falling over.

falldetectionevent = Chance to create a detection event when falling potentially revealing you while sneaking. Acceptable values: 0 or 1. 
The chance to create a detection event is inversely proportional to your sneak skill. Higher sneak = less chance to create event. 
If the player yelps when falling while sneaking then a detection event was created. 

horsefallheight = The difference in height you can change between checks while riding a horse. Depending on how fast the horses are in your setup you might want to increase this.

falldamagereduction = Reduces fall damage. Only when steep falling. Accepted values: 99.0, 90.0, 80.0, 50.0. (EG: 90.0 will reduce fall damage by 90%)

fallforcemultiplier = How much force to apply to the player when falling. Have fun ;)

whirlwind1height = First word of whirlwind sprint allows you to fall/climb an extra amount without falling. 
whirlwind1duration = How long this extra allowance lasts for in seconds. 

whirlwind2 = Second word of whirlwind sprint
whirlwind3 = Third word of whirlwind sprint

etherealallowance = How far you can fall with 'Become Ethereal' and not fall over. Default = a lot.

itemstripcountmin = The minimum number of items to try to strip the player of when falling.
itemstripcountmax = The maximum number of items to try to strip the player of when falling.
stripchance = The chance, per strip count, that an item is successfully striped from the player when falling.

stripforcemin = When an item is stripped from the player this is the minimum amount of force applied to the item to send it flying. 
stripforcemax = When an item is stripped from the player this is the maximum amount of force applied to the item to send it flying. 
Note: that the player, other actors or other collisons can hit items as they drop sending them flying further than the settings here. 

daystodumplostitems = How long in days before dropped items are sent to the lost & found shop to be sold back to the player.
Note: that if you are dropping a lot of items constantly then items can be sent to the shop sooner due to a limited number of aliases.
Changing this will only affect newly dropped items.

objectcollisionfallchance = Knocking over objects has this much chance of sending you flying. 
Note: Unfortunately because this is run on dialogue events it requires that you're not in combat and there's a friendly Npc nearby. Event doesn't fire as often as you'd think so default chance is high. 

furniturefallchance = The chance to fall over when jumping on furniture. Caveats: Same as above.

lostitemswidgetx = The 'X' position of the lost item count widget

lostitemswidgety = The 'y' position of the lost item count widget
