So I've got a mod that lets me overenchant various enchantments- and one of them is Feather Falling V, which completely negates fall damage at the cost of damaging the boots. However, when I jump off cliffs I still get the slowness effect despite being perfectly fine otherwise, which is kind of off-putting. Especially since one of the main entrances to my base is a roughly 30 block drop onto stone (has a ladder, but falling is faster and more fun).

It'd be nice if I could configure it to give me the effects based on damage, rather than simple height.

Thanks for reporting this, in the next update fall damage will apply effects only if player takes some amount of damage.