Due to Sepcrulcrave's Wyre Storyhour I'd have to say that Paladin's have the most potential for cool flavor.
Kai Lord said:It is utterly irrelevant whether the player is the best in the world or one of the worst. If the same quality of player portrays a character of each class, which do you find to be the most interesting in action? Have the coolest bells and whistles? Abilities?
Kai Lord said:Forget mechanics, which core class, in your opinion, has the best flavor? The greatest dramatic possibilities? The coolest combination of class abilities, whether they be feats, spells, or unique abilities?

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.