Ok so this could be difficult to implement, but I think it would give the game something unique, i think you should try to make a creation kit that allows players to create there own spells, weapons, npcs, buildings, monsters, races, classes, and quests. This would allow people who have finished the game to add quests, turning it from a game with like 60 quests (I'm not sure if it has more than that) to a game with hundreds of community created quests. Maybe you could have a system that allows people to share building templates. I really think that this would really add on to and expand the game.