Frontiers sounds like it'll add updates to its endgame content to make it more compelling to revisit after its initial launch.

There was some debate about a new roadmap for Destiny 2’s New Frontiers era which said it would have “raids and dungeons” in its expansions over the course of the year.

Revenant adds a new dungeon called Vesper's Host, though this one brings with it a new feature that's a first for the franchise.