A Tank for Every Class

So some of you might be aware that I'm loving the Glyph of Demon Hunting.  I think it's genius and I'm honestly kind of annoyed that you can't queue as a tank with it.  I remain hopeful that this is an ability that will open up in later expansions, since really, there's no mechanical reason why Blizzard couldn't make it happen.  A few tweaks here and there, and you're a demon-winged tanking badass.  Frankly the only tool that the pseudo-spec needs that it currently lacks is crit immunity.  Everything else is already there.

A slight improvement to Dark Apotheosis, and six out of the eleven classes in the game would be able to tank.  So what about the other five?  I'm sure there are many people out there who would love to mage-tank or rogue-tank, and I'm here to provide some suggestions as to how that could go down.

Hunters

Hunters are easy -- graft it onto the pet.  Make the tenacity pets better tanks and you're basically already there.  Give the hunter a few more aggro-generating shots that automatically transfer their threat to the pet, or more triggered pet abilities that use the hunter's Focus, and balancing shouldn't be a problem.

Mages

Go the warlock route -- give the mages a [Glyph of the Frost Knight] or something.  Have it turn Frost Armor into Ice Armor which would give a cool graphical overly and nice frosty effects as well as the armor amping and crit immunity.  Frostbolt becomes Frost Blade, give them a few cooldowns and threat abilities, an AoE aura of cold, and call it a day.  Sure, it's cribbed from the warlock abilities, but there's an awful lot of overlap between those two classes already anyway.

Priests

Another glyph -- archangel form.  They get a blazing sword, glowy wings, an aura of menace that debuffs and causes threat.  I envision these tanks as being more aggressively about debuffing your foes as well as mitigation -- they can take hits, but enemies also find their attacks hindered versus these beings of light.  I think this would be a good fit for a Discipline sub-spec, but an argument could be made for Holy as well.

Rogues

I think debuffing would also be the rogue tanking gimmick, along with a heaping helping of avoidance.  Their various stabs and cuts would hinder their foes' attacks, but crucially, only against the rogue.  I suppose this would also require a glyph, though you could arguably just turn Assassination or Subtlety into the "tanking spec" and call it a day.  It's not like rogues really need three DPS specs anyway, and historically at least one spec has been severely underrepresented in PvE.  

Shamans

I don't know about shamans.  They're the class I've played the least, so I don't have any good thoughts on the subject.  It'd obviously have to be a variation of Enhancement, maybe something tied in with the whole Earth Elemental thing.  Give them back their ability to use shields, I mean hell, they used to have an Enhancement tanking build.  Not like giving it back would be a huge problem.

I'm not suggesting that every class should be able to fill every role, if only because it's really kind of hard to envision any additional healer classes other than mage.  Tanking, however, is just a variation on DPSing, and every class can already do that.  Demon Hunting was a wonderful first step, but now I think the time has come to just go all-in and see to it that every class has a viable tanking spec.