Idea 1) The group is apart of a small military outpost. Initally they are given missions from a commanding officer to do what Pc's do best. stop some bad guys.
Idea 2) The group is apart of a smallish village who are away from the town for one reason or another when the village is destroyed by one means or another and now they must work together to find out what happened.
Now after the inital missions for the respective ideas, i have a twist for the campagin that wont matter which idea i go with. Its just the inital ideas. My worry is i want to provide these guys with a memorable experience and be able to incorporate as many different classes and playing styles as i can into the game.