As a long time supporter and podcaster of all things XIV I figured I should weigh in on some ideas, or more or less one idea that I would find enjoyable.
If others have already posted this idea, then I'm sorry for duplicating the issue, but I would love to see Dynamic content added into this game. By dynamic the thoughts I have in my head are a pack or a unit of beastmen/empire soldiers that decide to attack the city or a camp and everyone in the area can join together to fight them back (This joining together would happen naturally as players would have the option to join the resistance or group).
This shouldn't happen at a set time frame, but often enough that it makes the world feel alive and dangerous. Players who help would be rewarded so there is an incentive other then sp/xp to jump into this public instance. Anyway, think behest, but open to all, and not at the same interval. And it would seem very natural, and since the zones are so large, there would be or could be multiple public quests/instances/raids of this going at once.
The last part to this is that players would need to know if something was going on, so hopefully on the mini map and main map as well, you could see any public quest/instance/raid that was going on and go there if you wanted to join in.
Now, this might be what is planned for hamlet defense and perhaps something similar is already in the works, but I would love to hear some work back on if Final Fantasy XIV plans to support dynamic and public quests/raids/battles.