Which character to level?

Ok, so I really, really want a new level 90. Not going to boost it, but I want to see how far I can get before WoD arrives.

As you may know, I have 3 level 90 characters:
Theeriyi: Pandaren Monk (Windwalker/Mistweaver)
Toyosatomimi: Human Priest (Shadow/Discipline)
Quintella: Forsaken Priest (Shadow/Holy) (RP character, mostly)

My options are:

Yuyuko: Level 58 Draenei Death Knight (Frost/Unholy)
Gensokyo: Level 30 Draenei Shaman (Elemental/Restoration)
Toramaru: Level 27 Human Paladin (Holy/going to be Retribution)
Whispereith: Level 10 Night Elf Mage (Fire/going to be Arcane)
Rowenellia: Level 10 Worgen Druid (Feral/going to be Balance)
Momizi: Level 10 Human Warrior (Fury/going to be Arms)
Archanique: Level 1 Human Warlock (going to be Destruction/Affliction)
Bunnise: Level 1 Gnome Rogue (going to be Subtlety/Assassination)
Kaenbyou: Level 1 Dwarf Hunter (going to be Survival/Marksmanship)

I've been doing a few dungeons every day on Toramaru, trying to level her that way, but it's taking too long for my liking. Might go do some more in a minute though.
When I get bored of dungeons though, who do I play as? I'm leaning towards my Mage, Warrior, and Warlock, but then, my Rogue and Hunter also sound fun.

I'm so bad at this whole leveling thing.