Working on the idea of dungeons and stuff. Seeing like many people didn't liked it, I can bring something into light.
What about an area like the warzones of Tibia? Something that could need a service to people to get in, and get rewards. For people who didnt play tibia, its something like the Aga's hell quest, you enter every 24 hrs, for example, walk through a hard path, and in the end, theres a boss with interesting drops.
Since Aga's Hell is already almost the same of a warzone, I will use it as example:
Aga's "Warzone"
Can be done once a week.
Boss can change after seasons (for example, every 2~3 months).
Items can change according to the boss, or, could be more than one boss, and you choose it according to the items you use (you use x items, you unlock x boss, you use y items, you unlock y boss, for example).
Boss have interesting rewards according to the damage.
VR loots example: Mega stone (way lower % of dropping compared to spawning Megas, to avoid flooding megas), VR Cards, TM Cases, TM related to boss type, shard of something bigger (something that you have to gather 3~6 shards -according to the duration of the season- to exchange for a reward, this could be where you get the mega stone or VR card instead of dropping them directly)
Rare loots: Cheaper TMs, cheaper tm cases, rare cards related to the boss type, expensive house decorations (like lockers, toys, carpets, etc)
Regular loots: Rare candies, even cheaper tms, hds, regular cards related to the boss type.
The reason I suggest it is:
Back, when it was worth to make the quests together (for example, Aga's Hell, Frond Island, PoI/Inq) people were more friendly, cause everyone need everyone. Now, people can literally play for themselves, and fk off the rest of the community.
So making people team up again on a regular basis can improve the community feeling.
Also, with those rewards, economy can flow again.
The dungeon area can be used for this. Areas could look like Aga's hell, but I suggest the reduction of blocking stones, so smaller groups of people are needed. But I am thinking on 15 people groups to do the entire quest.