There is 4 main elements in the warcraft lore that shamans use. Earth, Water, Air and Fire. These would make perfect specs.
Earth - Role: Tank/Melee
Uses earth element to protect itself from harm and protect allies.
Water - Role: Healer/Caster
Uses restorative abilities of water to mend the wounds of allies. (Basically just Resto)
Air - Role: DPS/Melee Hybrid
Enhances his/her melee weapon with element of air to attack swiftly and lightning to strike agaist his/her foes. (Enhancement with DW or 2h)
Fire - Role: DPS/Caster
Attacks his/her foes with destructive fire and magma attacks. (Elemental shaman)
Basically all current specs would stay with re-skinning some abilities to fit more to the specs element, but shaman would get its long awaited tank spec.
This would also be the first mail-wearing tank class. Give me youre opinions on the topic and more ideas how to further develop this idea.

