Least played spec of each class in Wrath of the Lich King

Im currently working on a project in the Onyxia realm, playing underrated, least played etc. specs of each class, so far what i have been able to have been.

Warrior: Protection PvE, Protection PvP, Fury PvP
Death Knight: Blood DPS, Unholy Tank, Frost Tank, Blood PvP
Paladin: -
Hunter: -
Shaman: -
Rogue: Combat PvE (Early Tiers), Combat PvP
Druid: -
Priest: -
Mage: Arcane (Late Tiers), Arcane PvP, Fire PvP
Warlock: -

I know these might not be perfect in some peoples eyes but i would love some suggestions, i might even make video in the future of taking the specs into end game pvp/pve enviroment depending on how things go.

Overall?
Class : Most <---> least played. Focus on PvE end-game.
Death Knight: Unholy, Blood tank, Frost DPS, Frost tank, [Great Rift Valley] anything else
Paladin: Retri, Holy, Prot
Hunter: MM, BM, [huge gap] Surv
Shaman: Resto, [moderate gap] Ele, Enhancement
Rogue: Combat, Assassin, [The Great Unconformity] Subtlety
Druid: Boomi, Resto, [when did I last see a level 80 feral last time size of a gap hmm..] Feral
Priest: Disc, Shadow, [big gap] Holy
Mage: Fire, Arcane, [huge gap] Frost
Warlock: Demo, Affliction, [maybe there once was a fresh 80 that didn't switch talents immediately after they reached level 80 and got enough gear to do RDF so they queued with this spec by sheer accident size of a gap] Destruction

PVE BM Hunter.
PVE Elemental Shammy.