Out of the 3 choices you listed.
Don't go for hunter, they're the ez-class of WoW and are not really a challange to play.
Mages are a bigger challange pumping out some serious direct damage of the three you listed & are also very wanted for their buffs/food&drinks/portals
Warlocks are as easy to level as hunters but take more skill to play lategame, also with the right gear/spec you can litteraly own an enitre battleground with 1 backup healer.
If it was me personally I'd go for mage "LOLOL POM PYROOOO"
__________________
Playing Counter-Strike:Source / League of Legends
Waiting for Guild wars 2 / Diablo 3
Addicted to World of Warcraft
|