Some ad hoc thoughts:
I think that vinyl's distortions can be benign and euphonic, while digital's distortions can be perceived as un-natural.
Vinyl noise can make it sound wet, while digital lack of noise can make it comparatively dry.
Vinyl's speed imprecision can make it more relaxed and fluid, while digital can sound comparatively uptight.
I think that vinyl mastering is often better than that for digital because of the limitations it imposes on the engineer and because it is a different market.