Seen as though ive played every single char up to around 25 and higher in some cases and kept them i would say a rogue is! Put them in order that you think they're the most fun? ^_^
Thats what i would say is my order of fun-ness
- Rogue
- Shammy
- Druid
- Priest
- Mage
- Warlock
- Warrior
- Hunter
- Paladin