So... to clarify.

Send to the Cobalt shores to unlock Komura.
Send to Komura to unlock Kanayama.
Send to Wreckage of the Discovery 1 to unlock Deep Sea Site 5.
Send to Deep Sea Site 5 to unlock Purgatory.
Send to Mystic Basin to unlock the Concealed Bay.

Are those all the new sectors so far? Has anyone else found anything new?

Because looking at the nav charts, that covers the left side of the map, which makes me wonder if there's a branching path somewhere in the same vein as the airship paths. We don't have access to the gold sectors yet!