Every class should have something unique to serve the others.
I was thinking. Mages have portals/teleports which they can use to serve the other classes. Rogues has lockpicking to serve the other classes. I think more classes should have something to serve other classes as well outside of battles. I won't include Mage's conjure food because it is meant to help you in fights.
What should other classes need to have a service-skill (exclude professions and exclude fight-tools):
Death Knight: Path of Frost (Creates a freezing aura which creates ice beneath your feet, giving you water walking. Lasts for 3 min.) Their current path of frost skill changes into this.
Druid: Symbiosis
Hunter: Catch Pet (Catch Battle Pets outside pet-battles. Will be counted as loot (need/greed/roll etc..) in party when catched.)
Mage: Portals/teleports
Monk:
Paladin: Enlighted Weapon (a skill to lock durability on a certain weapon for 10 min. Only 1 weapon can be enlighted at the same time.)
Priest: Divine Reflection (When you die, your spirit will immediately reflected back to your body. When ressurected you cannot be targeted for 10 seconds by any player/npc or unless you start attacking yourself. Lasts 30 minutes and doesn't work inside dungeons/raids/battlegrounds/arena's)
Rogue: Lockpicking
Shaman:
Warlock: Summoning portal + Demonic portal
Warrior: Harden Armor (a skill to lock durability on a certain armorpiece for 10 min. Only 1 armorpiece can be hardened at the same time.)
* Green are new *
What do you think? What are your ideas?
Try to be original and don't put portal or teleport everywhere.