I wanted to suggest a idea for FFXIV to see if Yoshida-san would consider because I think this idea may (or may not work in some capacity). I was thinking about one of SE's older FF titles (specifically Final Fantasy X-2) and how they had this mega dungeon with previous enemies the protagonists fought and with a grande finale of a new original enemy.
Basically I propose is a type of Deep Dungeon that would take literally weeks to complete as it can't be done within a day. Ah but the question is what would be the incentive? I will get to that later.
Basically what I propose is this:
100 Floor Dungeon, but the twist is that each floor is huge winding maze that has no mini-map so you have to use either clues to find where you are OR the aid of other players that you'll come across.
This dungeon does not have a party formation, so basically anyone you come across you'll have to stick together to survive, and you can only be defeated in combat only a certain amount of times or else you suffer a penalty of sorts.
The save feature also would become more important due to the size and the time it will take to complete it.
Pomanders will not be as plentiful as they used to be, but will become that much more valuable if you find one. Maybe there will be one pomander that can help you in the right direction in the maze..
Each floor contains a boss that has previously appeared in the story OR from side-quests except the catch is they're more beefed up than before but with the same tactics except they can execute attacks much faster. They're merely shades of their former selves, but wouldn't mind having some revenge on you. (This way the dev team doesn't have to make new resources for enemies).
With each floor completed there is a gil reward multiplier that increases with each floor completion, and 1-3 random treasures. The maximum gil you can earn is 100,000 gil upon completing the 100th floor.
Now how would these floors be kept fresh when starting a new game? Basically the 1st floor and beyond will never be the same floors, so whatever floor you get is the one you'll have to deal with. So basically everyone's starting floors and beyond will not always be the same. Oh and you'll always be teleported to a random spot on the map upon starting the floor, so yes be sure to start manually mapping your surroundings DnD style.
Also upon completing this Deep Dungeon the first time you'll earn one piece of unique gear that will give you a slight advantage with special stats against the monsters only for this Deep Dungeon.
Also strewn about the floors of this deep dungeon is pieces of a powerful relic weapon, but they will not be very easy to find but the reward will be well worth it. Upon restoring the lost weapon you'll gain a boost against the creatures of the dungeon.
Now what story reason would it be to bring back previous enemies long since dead? Well I'll leave that to the devs to decide...maybe these are the souls that refuse to go back to the lifestream, should we call them The Unsent being led by a very powerful voidsent that looks kind of like Yu Yevon from Final Fantasy X? I think it would be pretty cool to face against some story enemies we only got to fight once, and never again afterwards (like Han'jit for example, would be interesting to fight a more dangerous version of him). Also another reason I want to make this topic, I would like for you all brainstorm on what would be a good long term content when we're waiting for other content (like more story, etc) to be released, I want to have people to have a reason to keep subscribing. The weekly loot while I understand the intention I feel makes content seem a lot less to do? Also I wouldn't want to see something like Eureka again (though hydatos was pretty interesting).
My idea is basically a mega deep dungeon, but I like to see what you all can come up with too.