My current top 10 :
1 (and by far) : Ill-Gotten gains !! I love the bird, the yellow-orange color...
2 : Jester
3 : Inn
4 : Farmland
5 : Lighthouse
6 : Outpost
7 : Altar
8 : Young witch
9 : Mystic
10 : Sea hag
Honorable mention : Harem (not so ugly !)
Hinterland is really the most beautiful set IMO : IGG, Inn, Farmland above mentionned but I like also the artwork of Oracle, Highway, trader and embassy. And the cornucopia cover is very graceful.