I would like to see treasure content be more integrated with the game (in your face, more) and bit more more hunter like...
So a few thoughts, but take them all with a grain of salt since I don't regularly use the system:
- Monsters and FATEs may drop maps occasionally (perhaps more accurately "chests"). Some may just be right there, others might be off the way slightly. Rather than taking up slots of a map these systems automatically trigger the chest (leaving the zone and a certain, long, duration would cause the chest to be forgotten). Using an archelogy like system (WoW, or other games) or hot and cold (chocobo) you can find these not too far off chests (wont be 10000 yalms on the other side). Loot from these usually being contemporary with a mix of buffs (like tomestones, and or buffs like exp buff, stacks with other exp buffs, free teleport buff, infinite sprint, potion like effects from Eureka, etc, naturally with durations that make sense).
- Suspicious gathering points that are visible to players that have a gatherer of said type of point. These you can see outside of that job, and denote a point which you can switch to your gatherer and get one of the DoH maps. Perhaps a function of time spent on the map, so it's like 0-10 minutes there is a 25% chance one will be 'somewhere' on the map, etc. Gathers might have a a radar skill for this. Your chocobo, if out, would make a Kweh sound when one pops, and can be used to help find location. Since I hope for chocobo hot and cold I would also say that you can opt to gather these locations with your chocobo as well (so like any spot can be gathered via chocobo, but if you didn't have your chocobo leveled to the right digging skills it's fine if you had the right gatherer- hot and cold mini game would not exist solely for this, but intertwine with many treasure map like features).
- Chocobos and or Squadrons can be used for old maps that are not current level (for old party maps). OR remove the sync to the old portals (of old maps only).
- Maps have some system in place to compile multiple maps together to greatly increase the chance for rare events (portals / items). Even if it's a not entirely perfect ratio (lost a little opportunity for the sake of convenience), so like if in 5 chests you'd get 1.5 portal / epic loot but there is now a way to compile 5 maps into one well researched map that's far more likely to reward you something nifty.
- Less static map system, chests not always in the same exact spot. If using hints, then not making a hint system that is so obscure that you still HAVE to look it up online (perhaps also using the chocobo hot and cold or archelogy like system). I'm sorry but the little demon in me can't help but know that the map has been pre-determined and look it up lol. Feels less like a treasure hunt and more like a treasure beeline. Also may introduce concepts like needing to obtain a key, so you find the chest and then the chest may or may not be locked (locked chests having better loot tables), with a hint on where to find the key (like X monster may have it or whatever). Naturally if the time to complete increases the reward to time ratio must be considered, I'm not suggesting a nerf to rewards (in time scale format).
- Going off topics of group finder. Makes me think of some of the stuff Diablo 3 had for a while with the whole shards for portal thing. So here you could create a treasure hunting group with the requirements to pick like that each person had a map of the same type (of whatever you put in) or "any type", when the group is put together you can ready queue to open a map and one is chosen randomly from the players (UI can be within PF, just some extra features).
Or if SE wanted to go far more wild I think a treasure hunter guild/finder concept could be built up, again I think bringing in concepts of archelogy would be neat (so like an adventurer's guild, with a section for treasure hunters). Then you'd have rankings through the guild, neat things associated with that, systems that can interlock (like chocobo hot and cold / archelogy, allowing some build up of the treasure hunting mini game and using it for other concepts), and also it might allow for some more QoL but complex systems for chests. Like by completing chests, even if you didn't get the loot you wanted, you'd get reward points to the guild- which you could then use as a safety net.