Just an idea of a new race for the next expansion. "But Dragons are a race, not a class" - well, Dragons disguise themselves as other races, the race of your Dragon char would simply be the race your Dragon assume. All races have the Dragon class.
Lore: Wrathion's plans didn't turn out the way he has expecting in MoP. Now he is determined to ensure that things will turn out the way he wants. Instead of relying on adventurers he wants to create an army of followers. But the Black Dragonflight is destroyed, so he has to think on something new. Since the expansion is about Draenor, he learns about the experiments with the Nether Dragons and decides to conduct a few experiments as well. His experiments create new Dragons who can change their color and use their powers in the other race form. After the end of the experiments Wrathion wants to infiltrate the Alliance and the Horde and so orders some of his Dragons to join one of the factions, depending of which race they desguise themselves.
Dragons can only use cloth. Their weapons are daggers, staves, maces, swords and wands. Also they would have of course a dragon form, but it would be quite small, similar to Wrathion's size, since you are young. But you could fly in your Dragon form when it's allowed.
Their specs are based on their colors:
Black - Tank
Red - Healer
Bronze - DPS
Thought that Blue would be kind of similar to Mages, and Green to Druids, so i didn't include them.
So, liked, hated? I'm not a big expert on the lore of the Dragons, I'm eager to accept suggestions.