I miss slogging out to odd locations and spending days farming up rare pets, it was hellish but when that pet landed it was the best feeling in the world.
No other game has even come close to being to add interesting little nuances like WoW, the pets were something that you could solo, but feel a sense of accomplishment about.
And of course the PvP, after WoW the PvP delivered by every other game I've encountered to date has paled in comparison.
The community was awful, the graphics were acceptable (hey if the games good you don't need to be all that pretty) and the raiding was abysmal. But the few things they got right earned them my sub for years and years.