Breakfast Topic: Could WoW fit new specs?

Right now all WoW classes have three specializations, except Druids who have four, and Demon Hunters will come in with Legion and will only have two. In the discussion of new class options, one thing that keeps coming to my mind is the idea of expanding existing classes instead by adding new specializations instead of a completely new class.

For example, what if Paladins got a specialization that was a melee DPS built around not striking down the wicked but instead on rooting out evil, an Inquisitor whose powers were much more focused on penetrating the shadows and dragging it to light? Or if the often discussed Runemaster was a Shaman spec, a tank who used runes and ancestor spirits to hold threat and survive punishment?

Not every class has an obvious new specialization, or would necessarily need one, but some classes like Warlocks (imagine the Netherspite Warlock, who taps directly on pure nether fury for her spells) seem like they could have a fourth spec pretty easily. Would you welcome it, or see it as diluting your favorite class?