Vanilla. My 2 favorite classes were the 2 worst, Shaman and Druid. Actually Shaman was busted in PVP when the game first came out, so much so that one of the CMs resigned or something for crashing out on the forums.
All the weapon imbues were busted, the meta was to run around with a dagger and a shield because Flametongue was busted and did full damage no matter the speed of the weapon.
Heck, I have videos of me open world PVPing Warriors with a sword and board as a Shaman and winning lol. (Post 2004, from 2020)
The game was so much more intriguing when it first came out. One of the main things I remember was the world PVP interactions. People would kite Kazzak and Lethon and whoever to Org alllllll the time. Also there were 40 man raids on Org alllllll the time, at least on Frostmane/Frostwolf.
Caster AOE had different coefficient back then. Five mages all spamming AOE on people could blow everyone up inside the AOE, it was hilarious. Back when you had to go to the physical portals to get into WSG when it first came out, people used to raid the WSG portal, not just the capitols.
It was amazing to see that many Alliance doing a thing together.
I also miss actually having scouts who had to go find the outdoor dragons and then you would have your entire guild camp by the dragon to see if another guild would come. Then the entire thing would turn into a PVP event, it was so insane. I remember fighting one of the dragons and Alliance literally at the same time.