Best you can expect from SE is quests/instances attached to timers (see Behest and Dynamis), Single-player story mode (see main scenario quests), or multiplayer story quests (See rank missions).

Letting players shape the world with their actions isn't exactly SE's forte, so to speak. They prefer to keep the game on a very tight leash. Dynamic quests which give players the ability to change the story of the server is something that just doesn't appeal to the collective mind of SE.