Still figuring out how to upgrade your port & what to upgrade first?
Please take a look at the following suggestions made by fellow Port-owners.
Crew-members are your best assets, they upgrade as you do more voyages with these crew-members.
Example: An Eastern Musketeer could start out at 350 Combat, costing 250 Chime & 80 Gun powder. After a few voyages, when the Musketeer has reached level 2, it has 420.. At level 5 its 525.
If these crew-members are bought early.. And used a lot... (Even on easy voyages where you don't really need em) They will level quite fast.
Also try to buy one or two Cyclops's/Siren Whaleriders.. With the traits: Rallying Cry. As this trait will improve all xp gained by 10% on that voyage (For all crew-members!) And use them whenever possible.