In its early conception there was rumors that Tall Tales was going to be a voyage overhaul. It is clear now that is not the case, and that's fine, but it means voyages are still very repetitive and monotonous. These are just my suggestions for how the voyages and trading companies could be improved.
The Order of Souls (OOS) and the Gold Hoarders (GH):
The OOS and GH voyages should be overhauled to essentially become procedurally generated, non story based tales. Though I can't comment on how easy this would be to implement the principal is quite simple; integrate all the assets, locations and mechanics (constellations, traps, caves, shrines, keys, etc) from Tall Tales into the voyages and have some means of procedural generation give players a book containing riddles, maps, constellations, drawings, etc. The end result for GH voyages would of course be finding numerous treasures and riches while the OOS would be a boss encounter, or rather a series of. The developers have said that they intend to release more Tall Tales updates past The Shores of Gold so every time a new tale releases the mechanics and assets can all be thrown into the procedural voyage mix. This would make voyages a proper adventure with puzzles and intrigue instead of a bland fetch quest.
The Merchant Alliance and the Hunters Call:
Integrate the Hunters Call into the Merchant Alliance. I like the idea behind the Hunters Call but in practice I don't think there needs to be a dedicated faction to fishing and cooking. Instead, Merrick and the other members of the Hunters Call would become Merchant Alliance NPC's found at all the sea posts around the map and the Merchant Alliance would become the ultimate passive trading company. Here's how it would work:
Cooked fish and such is sold to the Merchant Alliance as it would've been sold to the Hunters Call - could be worth a bit more money in my opinion.
Remove animal voyages and instead have cages spawn frequently near and on top of barrels - encourages players to collect them and bring them onto the ship and makes capturing animals a passive activity like fishing.
Introduce trapping - traps can be set using the cages to passively capture animals while performing other activities at islands. To do this set the cage down and a 'set trap' interaction should appear (requires the player to put respective bait in the cage - fruit for chickens and pigs, meat for snakes). Leave the cage and after one or two minutes an animal becomes trapped - can be released in case the player is looking for a particular colour and animals can also be captured hands on by the current in game method.
Trapped animals can be brought onto the ship as per usual and sold to any Merchant Alliance NPC - including old Hunters Call NPC's - for a profit comparable to the prices received for delivering an animal on a voyage.
The titles, commendations and skins rewarded for leveling with the Hunters Call can all be transferred to the Merchant Alliance.
Cargo runs should continue to function as dedicated Merchant Alliance voyages that can be purchased from any Merchant Alliance NPC.