I would wager that none is used more often than armenian, but none doesn't even appear above the fold.

IMHO the top-ranked results for list-style could be:
none
inherit
initial
unset (currently not included at all)
url()
... and then all the shapes, in alphabetical order.
More generally, is there a way to rank suggestions by popularity instead of alphabetically? Chrome's usage counter lists properties by popularity, but not values. Is that info publicly available somewhere?
If you're receptive to this I can make a PR.