The holy trinity of the mmorpg genre is certainly a staple in tons of games, with most grouped content requiring at least a tank, a healer and a few dps.
But wouldn't it be better if it was further expanded? Adding more roles and diversity and allowing players to have different tasks in an encounter could breath fresh air into the game. They could split some pre-existing roles or create new ones.
Here's some ideas:
Controller: Guy who's main purpose is to apply crowd control to adds so they become easily manageable and burned down quickly. Ex: Druids could shape the environment to block enemy paths or force them down another. A mage could freeze a pack of mob, etc.
Off-Tank: More than just a secondary tank, this guy deals damage and excels at tanking little adds while the main tank takes care of the beefy boss. They help protect ranged characters and healers. Somewhat a hybrid between a tank and a dps. Ex: A fury warrior who enrages the more there are enemies around him, increasing his damage outputs as he shrugs off the pain.
AoE DPS vs. Single target DPS vs. Ranged DPS: Sure, some class already excels at one or the other, but they could further increase the gap by making some class inherently better at dealing damage to one priority target, while other classes are better at burning down multiple foes at once. Ex: Rogue that assassinates important adds while a warlock melt the cannon fodder and the marksmanship hunter kills archers on a balcony
Buffer/Debuffer: Someone who actively tries to find a way to increase damage received by the boss, or increase the damage dealt by his allies. Ex: Elemental Shaman that throws a fire totem near the boss, which creates a lava pool under it and make it vulnerable, and throw an air totem near melee dps, which imbues their weapon with thunder. But he must throw thunder bolts to power the air totem and lava burst to the fire totem when they deplete.
''Skill Monkey'': Not sure how else i should call this one, but it's the guy who can give you an advantage before the fight even starts, their utility in a fight might be limited, but the utility they bring to the group that makes it worthwhile. Ex: A rogue who disarms traps that would otherwise reduce your max health by 25% for the remainder of the dungeon/raid and then unlocks a bonus chest at the end, a survival hunter that scouts ahead and give knowledge of the enemy to the group, increasing everyone's damage by 10% against scouted enemies while also marking incoming enemies on the map.
Sure, some of these might exist to a lesser extent, but they could expand over these ideas and create new encounters, dungeons and raids which are more elaborate and lively.
WoW has always been a war about who has the best dps, who's the best healer and can tank the best, but if each class had their own unique utility (other than just unique buffs) suddenly their dps/hps output matters a lot less.
Also each of these roles would be secondary and not mandatory for most content except maybe high end content. They'd offer different ways for a player to participate in a group. Much like pen and paper rpg like Dungeons and Dragons. You sure can build a pure tank or be a rogue skilled for the trade, but none of these are actualy a requirement for a group. Everyone can bring something to the table while not competing against each others for who performs the best.
Tell me what you guys think!
Also i've somewhat been inspired by the mmorpg Neverwinter which has seven distinct roles: tank/off-tank/healer/controller/single target dps/AoE dps/support