Must complete quests in a row (without dying) in order to achieve greater items. It would make people play harder who aren't playing Hardcore, because the Quests would be available to those in non-hardcore modes.
Or, a quest where each individual player must do something on their own within a certain time, and if they fail, the whole group fails. Everyone has to succeed in their own individual quest to complete the Team Quest. It would allow more emphasis on the MMO portion compared to T1.
Eventually, each player could possibly end up together (like choose your own adventure) and fight a final boss. Just trying to find ideas that could add something new and inspiring for T2! I would definitely look forward to it but then again, there are other important issues to be addressed first.