Eastmoon ruins for sure, don't bother going anywhere else. In less than 30 mins. I got all 30 ornaments, 7/10 enforcers and 3/10 brutes toward the Dunemaul Compound quest, plus about 50 silver and 7500 xp on kills. Add the reward items and the 6300 xp at the end and this is one of the better ground collection quests in the area. The mobs are spaced very wide, don't path or add much if at all, and they just stand there like trees and take their punishment (a nice break from a long day of chasing Southshore pirates thru crowds of adds). They're dumber than a box of hammers too. You can literally stand in front of them collecting ornaments right under their noses. In most cases if you're only after the ornaments it's easy to sneak up and collect all 30 without having to waste much time fighting.