On is unique in that there is a suitable dock site close to the ship entry point, but it's far away from "where the action is" -- requiring a lot of ground transport.
The "approachway" to the first dock is the distance from the entry point to the dock -- but the approachway to every other dock is from the last dock to this dock. (This assumes unconnected docks -- no way to walk from one to the other without going off the road, where a ferry counts as a road.) The objective is to keep the approachways short.
My On had the first dock on the north island, and the second on the big central island -- right across from each other, and right on the default route (the route ships would take if they weren't stopping to trade).
Traffic at the first dock WAS chaotic, but I was only trading one good there, so ships were in and out quickly -- regardless of who was going first, and who had to wait, and so on. But the second dock, with a short approachway, was orderly.
There is a critical distance between the two docks which I haven't exactly figured out yet; and of course the order is important -- build the first dock first, and never let it run out of labor (or it will be put on the end of the list).
I was able to keep traffic flowing smoothly and keep most goods near to where they were produced/demanded.
Henipatra
[This message has been edited by Henipatra (edited 11-15-2018 @ 01:56 PM).]