I mentioned this in an earlier post and wished to briefly revisit it.
What if the OW took some cues from the EVE: Online concept of High and Low security player areas? If you're not familiar with how it works, essentially this: in High security (+1) space, human players are able to attack other human players, but at the cost of immediate interdiction and retribution from NPC police called "Concord" that are effectively impossible to destroy. So attacks against players in "Hisec" is extremely rare to the point that players interested only in PvE are able to do so in peace. Everyone can still transit through Hisec space and that's where most trade hubs are located.
In Low security space (gonna combine EVE's Low and Null into just Low for the sake of argument), players are free to attack each other without any retribution. However, this increase in player risk also results in far more rich rewards from PvE activities -- missions, trade, resources for crafting, etc.
Where EVE really nailed it was how they connected the areas of space. In order to trade effectively, players had -- but were not required to -- transit across danger areas of low security space. You could always take the safer route, but it cost you time. This areas of transition between high/low security were great hubs for PvP amongst willing and unwilling players alike.
How would this work in Naval Action? Well, how about trade lanes? Say, for example, you wished to move Hemp from Gustavia to Ponce (just to use a random example) to sell for a huge profit. You consult your map and find your nation's Admiralty has established a trade lane in that direction. If you are attacked in this trade lane, your battle instance will populate with the overwhelming force of your Admiralty's navy (response would be, say, 2x-3x the BR of your attackers). You're still in a pickle, but you have help.
However, unlike EVE, you have to physically navigate the trade lane effectively. When in the trade lane, your UI will reflect that in the way it does in Ports (i.e. green, controlled by X nation), but there are no other navigational aids. You need to chart your course well. Should you stray outside the trade lane, in a storm or at night, or the wind fails you and you need to tack significantly, your trade lane indicator will disappear and you're now vulnerable to attack. Pirates and enemy navies frequently ply the seas around trade-lane chokepoints, so if you intend to arrive safely, you need to sail carefully -- not just point your ship in a cardinal direction and grab another beer. (Admit it, we all do that all the time.)
These trade lanes could connect the entire OW, but not completely. In specific areas, perhaps the trade lanes have gaps? Or perhaps players could contest trade lanes in fights against Admiralty AI fleets? Thereby cutting off safe trade to key ports.
With successful navigation of a trade route comes reward, naturally -- so moving specific goods between nations should be a profoundly profitable endeavor, just as it was in the Age of Sail. Perhaps the presence of an ongoing or recent Port Battle should briefly spike the price of goods the NPCs will pay in order to encourage players to move goods into particularly dangerous waters.
What are you thoughts? I really think that an essential component to this fantastic game's long-term success is a more articulated trading system. EVE has shown that there are legions of players interested exclusively in accruing in-game wealth. While I fully acknowledge the heart of this game is the combat, I feel such a trading system would be relatively easy to implement while being inclusive of players not interested in such gameplay -- it could also subtly encourage risk-taking and, ultimately, strategically laid ambushes and ganks against trade routes, a element entirely consistent with the game's historical context.