This is my opinions of what lore characters shouold be added in-game for World of Warcraft: Cataclysm and why (and what purpose they would serve):
- Rehgar Earthfury: In lore, it states that Earthfury is now a shaman. With Cataclysm introducing the Earthen Ring as a new faction, Earthfury could be a prominent leader of the Ring. If the New Council of Tirisfal is ever made into an in-game faction, he could be the Council's Orgrimmar representative. In-game, I'd see him as a quest giver either as one of Thrall's advisors in Grommash Hold or somewhere else in the Valley of Spirits or the Valley of Honor. Earthfury would probably give much of the Horde quests for world events revolving around the Elemental Plane raids, if there are any. Most definately a quest-giver during the Cataclysm world event.
- Broll Bearmantle: He already appears briefly in-game in WotLK, during The Battle for the Undercity, but I feel he needs a bigger role. Similar to Earthfury in Orgrimmar, Bearmantle could be a quest giver either in Darnassus or Moonglade for the Elemental Plane world event raids if there are any. If the New Council of Tirisfal is ever made into an in-game faction, he could be the Council's Darnassus representative.
- Garona Halforcen: Since she is the mother of Med'an and is also a member of the New Council, she would be a prominent member of the New Council. I could see Garona as a quest giver (featuring a revamped model from the one she had in the original WoW beta.) wandering the same path that Rexxar did (from The Charred Vale in Stonetalon, through Desolace, to The Twin Colossals in Feralas) before he was moved to Outland. She'd be friendly to both Alliance and Horde players. Also, with phasing involved, Garona would appear during the Cataclysm world event and other world events, she'd appear at the New Council of Tirisfal encampment and at the various Grim Batol locations.
- Valeera Sanguinar: Also appears briefly in-game in WotLK, but she doesn't do anything, unlike Broll. Can see her also as a quest giver in Silvermoon, but not for the Elemental world event raids, maybe the Cataclysm world event. If the New Council of Tirisfal is ever made into an in-game faction, she could be the Council's Silvermooon City representative.
- Med'an: Leader of the New Council of Tirisfal, whose original motive was to combat Cho'gall and the Old Gods during the Alliance and Horde's fight against the Scourge. Now that Cho'gall has returned in Grim Batol and has allied with Deathwing, the New Council could be the main quest hub for the Grim Batol events, raids, and quests. See him as a quest giver. Also predict that, if this ever happens, that the New Council of Tirisfal's base of operations would be a currently unnamed keep or camp in the Twilight Highlands.
- General Turalyon: Although it would be a job to explain how he got back to Azeroth from Outland, Turalyon needs to make his long-expected debut. I could see him as either the leader of the Alliance forces and major Alliance quest giver for Tol Barad, OR (I had an idea where both the Alliance and Horde could send expeditions, similar to the ones in Northrend, into Deepholm for Cataclysm) the leader of the Alliance Expedition in Deepholm.