I'm not sure if anyone is familiar with the X Series but I wonder if it would be possible to apply one of the mission chains to Naval Action.
I'm referring to the "Treasure Hunt" mission chain that you get once you've explored a certain amount of sectors*.
I think it would be fairly easy to create and would force people to know locations by sight rather than teleporting from one port to another but would require a bit of imagination to write up the necessary wording for the quests. It could be done in a number of ways, via message to inbox or like the "last known fleet location". It could be done every quarter of a year, month, week or day depending on how long you made the chain.
So an example.
You receive a mail saying:
"Captain, one of our agents received a letter from an anonymous source stating that they had learnt of the location of a rare ship that had become beached. The letter does not state exactly where he is but he has left breadcrumbs for those determined to find this potential treasure. The first step is to meet his agent at the solitary fort between two capitals."
So you go to Fort Baai.
You receive another mail saying:
"We found the source's agent whose name was Captain Cotton. He wants to be paid 10 mill gold for information but during the course of the conversation you learn he lives on an island and that he master lives on an island to the west. We can either pay him for his master's location or try to find it ourselves so we can speak to him"
So you got to La Bermeja
Then you get another:
"You finally find the anonymous source. He asks that you help him decorate his house and wants 5000 gold pieces and some famous 6 Parisian Furniture. Then he will reveal the location of the hidden ship"
You bring it obviously
"The master thanks you for his home improvements and gives you a map, remarkably similar to the one you already have. Unfortunately he has spilt some tea on the part south west of Bermuda. He says that it is around that area".
Off you go to dock at the hidden island and dock up at Rum Cove and you receive a Hercules note, in this instance. First come first served and only one person can complete the chain.
You could always make it specific to sights but for the sake of ease I used easy examples that could be found with the map and trader tool but you get the gist.
More people further out to sea, more potential content.
Lazy people who don't like traveling miss out. Oh noes.
*A walkthrough of it in X3 https://roguey.co.uk/x3tc/help/spike/treasure1.php