There are multiple indirect gains out of the proposed format. Some of them are gold coin based. But not all gains are gold related. I understand that your piratey (deep-down) heart desires more shiny coins and I can only blame this.
We also need to put on the table the preliminary part of the feature. It is too early to add anything too significant on the table. Actually, controlling the port traffic on a fee is quite big already for my piece of cake. If I also include in the deal the dynamic type of the whole process, then we should not even care about any rewards. It's a free market again and the two sides will dictate what is worth of it every time.
If we ever need to add more things on the table, there is nothing easier. Here are a couple of ideas without even pushing my own creativity:
-Add extra danger penalty to whoever does not pay the toll.
-Add extra influence penalties (to winner and loser)
-Add further honor/hostility penalties (you failed to defend your port eh? The country officials are not at all happy... )
-Add control to exports too (with the proposed system, goldsmiths on port can work....)
-Add toll fee to every attack done at the port
But again, it's too early to make this feature this significant. There is plenty of time later. As someone else noted, there are features like Plantation that will also play a role. More are coming (Port Buildings anyone?). If we rush so early on, there will be greater trouble later - does anyone remember ( our perhaps single) the debuff - commonly called wimping - on fishing? Many were disheartened over this - many might still be while some others might still be waiting for the special ship (which is a future possibility after all). Although the fishing feature is still important and useful, despite the wimping. However, it left a bad taste. In the contrary, Skirmish started with low expectations. Building it stone by stone (more stones are surely needed) we have improved it in the right time and way, succeeding our "schemmy" plans to manipulate the game in the way we believe it will be more enjoyable (a lot more fleets with danger than before in this case).
Similarly, there are "schemmy" plans here. For instance, getting some bigger ships out. Sooner or later, this will be done. Or persuading the big players to raise multiple big war fleets
AND enter the current fight on current disadvantageous (for them) game factors. I think the first part is almost done. Now we mostly need to
push them to use them. Such players do not really care for gold. They more care for fame (I find this healthy btw) so I think that current Blockade plan will work anyway.
For the record, these "schemmy" plans are not that schemmy to those that constantly follow my posts in the forums. For example Shadowood who does, is well aware of them. As everyone who just read this post, is now also aware. Well done! I am talking to you!