Originally Posted by
Ehache
Rather than a whole new class I fell like a lot of great niches in gameplay could be filled by a 4th Spec option for a few classes, Demon Hunter comes to mind as a perfect 4th spec for Warlocks, a pet-less, dual wielding Tank or Melee DPS. With this addition I can see them opening up Warlocks to Nelfs, and could easily add in additional races with some Lore handwaves.
Shaman Spec: Earthwarden
By fusing with an Earth Elemental, the shaman's body erupts in rocky outcropings. An Elemental hybrid, preferably more like a priest's Shadowform, than Warlock's metamorphosis.
Mail Agility Tank
Deathknight Spec: Necromancer
A ranged Spellcaster and pet class, the Necromancer uses endless streams of suicidal undead minions.
Plate Int DPS
Hunter Spec: Packmaster
Able to summon 2 non-exotic pets to work in unison, this Hunter leads from the front using melee weapons. Powerful control over threat and mitigation as pets absorb damage and spread it through the pack.
Mail Agility Tank
Mage Spec: Timewalker
In the heat of battle these Mages have the ability to create pockets in time, saving those inside from damage, or rewinding time to undo deadly harm.
Cloth Int Healer
These are just a few workable(?) ideas but I'd love to hear some feedback.