In WoW the zones I loved the most were Westfall because of it being the first area with a dungeon, alot of people looking for group, alot of talking and ofcourse the Van Cleef questline. STV because of the chat and the beautifull eviroment, and I somehow always loved to collect the pages of STV book. Tanaris was one of my favourites, no idea why really. Winterspring I loved because of the beautifull eviroment, but hated the quests. Guess for me it boils down to having enough social atmosphere in the zone, quests with storyline instead of the normal "Go pick a berry from a Talbuk sh1t and bring it to me". Sad part is, Nagrand actually had that kind of a quest, so did Hellfire Peninsula. Made me wonder at times what are the blizzard developers thinking when they want the players to go dig sh1t bare handed. I don't mind big zones at all, as long the feel of the zone is good. Feel of danger, feeling of united questing towards some bigger goal, with good side quests here and there.