I'd like to see the Adventurer's Guild become the central organization going forward with the PC returning to more of an adventurer/explorer role rather than The Savior of All Creation. This would allow for all sorts of cool interactions, horizontal progression, and a revival of the GC Squadron content. Rather than being forced into Trusts with MSQ characters, let us recruit and advance with our chosen compatriots.
The Students of Baldesion could fill this role as well as we work to rebuild the organization as it's also an adventure/exploration/field research based group.
6.1 is a good time to start wrapping up all the Scion character's stories and get them all out of the way for 7.0 and onward. They've had their time in the limelight and need to go away.
Things to do over the next 10 years:
1. Update the character creation system
2. Update graphics or at least giving people an option to go with higher quality settings along the lines of mods while continuing to give people with lower-end machines the ability to play with current settings.
3. Revamp the Deep Dungeon system to create an endless set of floors to progress though like the tower in Danmachi/Is It Wrong To Try Picking Up Girls In A Dungeon? Rather than having the floors all be the same aesthetic, use the environmental assets available to create unique floors each with it's own floor boss to defeat before progressing to the next. This would be something akin to a floor looking like the Black Shroud with creatures found in those zones and a Morbol floor boss, for example. I'd play TF out of something like this and am willing to bet a good portion of the player base would too; especially as an endgame/mid-patch option outside of raids. Just make sure to do away with the ethereal weapons or whatever they're called; let us use our own gear, get usable upgrades appropriate for the floor difficulty, and earn a non-limited currency with which to purchase gear and supplies.
Making each floor procedurally generated would be ideal.
4. Update the glamour system to accommodate a much larger amount of items or preferably, use a catalog system similar to LotRO and WoW.
5. Housing. 'nuff said.