I like a lot of ideas so far, though wanted to comment on a few.
For the ul I was thinking maybe a single family or maybe 2 if there could be enough information provided for them rather than fleshing them out fully. Maybe it's even a minor family limited mostly to the Blessed Lands / First City area. If there'd be too much cultural information required, then I agree it's too much. The same applies with the val'Sungha, though that would be cool.
I'm not in favor of the minor artifact suggestion as that feels like spending money for mechanical advantage. With the other options so far while they open up new opportunities or combinations (combining psionics and ss'ressen for example) they're available separately. Even something like Ashen Hide is likely balanced against other available races.
I like Tori's suggestion for official canon NPC status for a character, potentially even a former character. I'm toying with the idea of having one of my characters from the last campaign own the business in the first city or perhaps his child and in so doing make the previous character canon.
Many of us that play, play because of the story far more than the mechanics. That's always been Arcanis' strength. Tori's suggestion for the tailored "hidden" reward also sounds intriguing. Very likely a double edged sword, but fun nonetheless.
Another idea I had was for Henry to put up certain answers or information as target goals. He would provide the list or a list to be voted on and then once those are achieved decide how to provide it. Consider for example him telling us that X from the Codex is false. That certainly opens up a lot of questions of what is truth, but would be very interesting to know. Ygg = Anshar is confirmed, what about Belisarda though?
Lots of possibilities.
With a sweep of his...
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