Qwerty, ye be thinkin' up the same line I am - I can wait on port forts and cannon. We already have the means to create armadas.
I've ran these ideas by several mates in Avonmora - here's the concept:
National Navies, ships built by the nation's subjects and put into His/Her Majesty's service. Once in service, these would be put under the command of the Governor(s) and Dukes as decided by the King/Queen. A hard limit of say 1 to 3 fleets could be under each Duke, Governor and the King/Queen.
The orders would be simple, such as:
1) defend all fleets against skirmishes and/or plunder;
2) defend *said* nations against skirmish and/or plunder.
3) Attack *said* nations in a certain port
4) Attack *said" individual in a certain port.
Simple Missions. National Fleet would be limited to stay in one port. These fleets receive the same DR as a normal battle fleet, and if defeated, bounties paid from the national treasury. Bounties would be higher, perhaps double those of normal battles. Upkeep would be doubled. For levels lost in battle, the upgrade to level the ship back up would be doubled - all from the national treasury. Fleets put into service without orders will have upkeep costs 10 times the norm as bored sailors on shore leave tend to be an expense to the crown.
The ships in these fleets could not be captured or sunk - they would be destroyed, as the crews would burn them to the waterline. (Pirate Flag ships cannot be put into national service.) A flotsam and jetsam bonus would go to the victor.
Voodoo is the tricky part. My thoughts are National Fleets would be subject to any voodoo that can be cast upon fleets or ships, but not voodoo targeted at individuals, such as HNs or Fugis, disfavor, but definitely to Fire Ship, Leviathan, kraken, etc. The duke,governor or king in command of the fleet would be notified of the voodoo cast and would be responsible for clearing the voodoo - no one else would be able to do so.
Therefore, in order to put these ships on the plunder screens, one must determine what Fleet's orders are. Once known, a gambit to get them to engage will provide combat. No need for voodoo in this case....
To budget the service, the National fleet would engage until a certain bounty has been lost in battle. It would be counted against her winnings, which would be normal. All winnings would go into the national treasury. Or perhaps when a certain DR is hit, the fleet stands down to cool off until orders are re-issued. (and the upkeep costs of 10x normal kick in as the crew takes shore leave!)
When the tie comes, these ships, along with every ship in Avonmora, would also be subject to national disasters, such as hurricanes, gales,sunami, etc. (When these are brought into the game).
A note on the gossip page shows a National Fleet is present in the port area, although not what the ships are, nor would they be subject to skirmish...perhaps. Wanna skirmish with the King's armada?
It is an idea to put more ships to sea, and provide a means for diplomacy to have some teeth.
These would be national fleets - the primary job is to handle the national interest. A division of defense and policy enforcement. The only cargo on board would be cargo that was on them when they were put into service. Once in service, the cargo becomes part of the ship's resource for bounty, etc.
Individuals flying national flags would be separate, and should have different perks. One would be the ability to gain (or lose) influence in ports through trade and combat. One way to do this would be to convert fame to influence instead of gold coin - but that changes the topic of Naval activity.
That's the concept, the idea. We already have ship and fleet parameters for ships and mechanisms for battle. I KNOW I have not covered every aspect or weakness in this idea - but it is an idea I like as it joins Nations to the seafaring aspect of PG.