There was an accepted suggestion on gitlab about a neuro rework, which basically stated that when mobs are hit with neuro it causes a build up of chems in their body, which metabolizes slowly.
The effects would go from being totally fine at low Us, to moving slowly, getting blurred vision, and eventually being stunned for a longer period of time. No insta stun but when you do go down you stay down for longer.
Also played around with in that suggestion was the idea that targeting different body parts would have different effects - eyes, blindness, hands = dropping stuff, feet makes you slow down a lot.