Digital Crown is great, but there's one improvement I'd make - as you're scrolling, you'd get haptic feedback between views (very light tap) and when you're at the end of a list (stronger tap or multiple light taps). This would simulate 'notches' in the Crown.
That'd drive me insane. Like the "clicking" noise that people liked putting on scrollers a while back. There is already a tap if you try to go past the end of a list.