Anything which keeps players engaged with the game. Guilds have been a good start but that should have been there at launch.
2019 Content Needs:
Tools to let players/guilds create interactive content like branching storyline quests, mysteries, haunted houses, etc. Also expand signs to include in-game lines to make maps and runes for interactive content. Also signs on which can be placed in-game screenshots for art contest and interactive content creation.