It should be a standalone story so not tied to field content or any other specific content. I don't think the idea of gathering a specific currency like Manderville is bad, but they can adjust that by having the currency obtainable a variety of different ways and we can choose our path. Kind of like the crystal sand step for anima or how WT works each week. Tie the currency to some roulettes, some new field content, some PvP, some crafting, and it will still give the feeling of working toward something that just tomestones is lacking but will also be adequately future-proofed.