I like the idea of adventuring guild (content), but I'm not sure about it needing to be a separated content. Hunting log being turned into a log related to hunts at minimum would be nice (catalog and perhaps add 'extra' reward the first time you kill a hunt, can also be used as a more convenient interface for the hunting bills). Like monster arena could be a content for all jobs, including limited. Where the circus thing is more of a puzzle and show with steps then the arena is more like say the FFXV event (MSQ solo stuff, etc, but naturally it scales to the more aggressive ends as you tier up, unlike say the MSQ which is meant to be accessible).
So like the idea of traits could carry forward still, but rather applies in general. Reminds me a bit of the passives you can earn from Garrison in WoW.
This whole adventure content could then take a slight revamp to the leve system and absorb it, adding a bit more leg for the system to stand on / together. May, if really wanting to tie everything into a UI panel, even bring treasure system into it (and chocographs/alchemy?).
Just seems like jobs are for making ships and what you're describing is more the sea (if jobs traverse, as a ship, through content like MSQ/open world as a sea), so then making the sea another form of ship seems like a way to limit the means of interacting with a large body ported into a small space- which would, I think, rather more naturally exist as just.. a large body with the means of 'other' ships being ported through it. (Aka, at least to me it seems like the ideas could just be made content rather than a job itself, and you could have progression systems still, just doesn't need to be a 'job', my imo lol

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