11 classes in wow, all with there own unique purpose in the game, and all with there own unique lore.
going from potentially the most evil class to play as, right down to the most good guy class to be, what order do you put this is.
to make it easy
You can use examples of characters in the lore who being the class they are acted upon such good or bad methods.
Most Evil > - Warlock - Deathknight - Rogue - Warrior - Priest - Mage - Hunter - Shaman - Druid - Paladin - Monk - < Most Good
I consider monk more good then paladin, since I've yet to see any real story of an evil monk or an monk who uses his power to harm others for the sake of it, even paladins have used the power for the wrong reason sometimes.
Warlock obviously most evil since they allow themselves to give into evil and corrupt magics, deathknights, well pretty nasty, didn't have a choice.