I’d like to propose that you do some zone revamping and add more sandbox features to this game.
First, I would take some of the story quest chain elements and put them in pocketed areas that remain theme park style and unchanging just to introduce people to the game, and keep that flow and path to max level. Maybe even make some of those pockets neutral/not ownable by players but by the npc/story. Outside of those areas, the zones should be more dynamic to add more post-max-level content. The corruption portals are a good start towards that, but I also feel like open world events that emanate from unmanaged portals could also be interesting and shake things up.
Second, as you level up the city and manage the zone events and portals, it would be interesting to see the zone itself improve. Like a guard house that adds NPC Guards to patrol the roads and keep them free of creatures and protect like-faction and high reputation travelers. Corruption oozes clear up, and farms and villages become usable by the controlling faction, allowing you to “share crop” essentially temporarily renting the farm to grow foods and herbs. Fail the world event, or leave portals too long? Then the ooze and corruption takes over, npc’s go mad, guards can’t patrol without dying to invading mobs, etc. Maybe the roads become oozed and you don’t get the travel speed bonus.
Third, PVP trade. It felt like with separate banks and original trade post that there should have been a pvp trading mechanic. Maybe certain cities need items from other cities that can only be fabricated there, everfall foods, everfall guard weapons and armor, etc. You flag, make the requested item, and then you must deliver it without dying. Otherwise, a player could take this “city npc only” type item from you and turn it in themselves. Risk vs reward with higher rewards the further you must travel with your goods.
I realize that pve invasions and pvp territory provides some of the “world event” content. But being limited to 50 people, and mostly an end-game content, I feel like open world events would add more randomness and stir up a wider audience. You might even do open world pvp events, where a faction hero shows up in enemy territory. You could then flag up and help an open world fight between faction heroes.
Give people more reasons to pvp flag and travel, in a more sandbox environment: people become the content. Adding extra reward for gathering while flagged was a good start. keep adding