MSQ improvement suggestion: please consider guild wars 2's system
l know l said this many times in my replies to others, but l think l want to make a thread. So, this is my understanding of GW2's system. Assuming people all have bought the expansion, the instanced content only checks party leader's story progression(not sure about the person that's not at max level, probably level needs to be at the max).
For the new area, you can buy "teleport to friend" and teleport to someone on that new map and start participating in content in that map. And maybe you can charge 1M gil to buy the item, then let it have like 5min cooldown and need 10000 gils per use to act as gil sink(this is my proposal, not something gw2 does).
l think this is a decent system ffxiv should consider if there are not too much technical debt that prevent its implementation