Those numbers may not mean what you wish them to mean
Basic assumption: The game should last no less than 8 turns and have no more than 12 turns for a 4 player game.
The current map graph has 36 nodes and 62 edges.
Gut sense suggests that no more than 75% of edges should be claimed in a typical game. ie ~47 edges. Across 4 players that’s 12 edges per player per game. If players have a maximum of 2 explorers and gain the second explorer by turn 3, that suggests a total of 13 routes per player per game, assuming no lossage and an 8 turn game (optimistic 8 turns?). So far this seems reasonable.
If claiming a route produces a cube on each end of the route (as is the current thought), a fully built network will contain 124 cubes. A 75% built network will contain ~93 cubes.
Assuming that explorers equals proas (which doesn’t work, but bear with me) means that an 8 turn 4 player game delivers 64 cubes or, ideally, ~5 satisfactions per player or a more probable 3-4 satisfactions per player. given partial inefficiencies. This is a problem. The average number of satisfactions should double that. The only real way to address is to decrease the satisfaction definition or increase the number of deliveries.
Moving to a DiscoInferno? (Ted’s AoS expansion) style delivery pattern (chained opportunism) delivery rule would increase the average number of satisfactions per player per game to 5-6, assuming that cube production keeps up (not clear). This is better but still within the range of a problem. Cube production rate seems the main throttle at this point. There simply aren’t enough cubes available fast enough to sustain the deliveries.
A possible solution is to put 2 cubes on each island during setup, plus one at the end of each route when claimed. I’ve not done the stats yet, but that smells about the right rate.
Assuming a similar proa growth curve to AoS Links growth (which breaks above assumptions) and assuming that all steps are bought with fish rather than passed deliveries gives ~82 fish transactions per player per game. Mapping that against claimed routes gives an average personal fish production of 26 fish per player per game. This is clearly a problem: costs are unsustainable. A possible address is sustained fish income. Certainly the extra drain of Kula items on the fish economy is grossly excessive. Approximately 4 times as many fish are needed in the game in the ideal case. Practically this should mean ~6 times as high a production rate in order to sustain kula trade as well.
Currently fish are earned when delivering over a player’s own route. The player produces fish when delivering over his own route and pays fish for delivering over other’s routes. This is insufficient given the current expenses model. Simply increasing production by 6x is uninteresting. Without an expenses model moving fish to a standard exponential growth curve makes the end-game uninteresting (at least WRT fish) due to largesse. Adding expenses ala AoS may be too derivative. More likely another modestly inefficient sub-game to generate fish is required.
This is going to require thought. If more fish are to be produced, what is to be sacrificed in order to produce fish? Advantage? Resources? Opportunity? Position? Tempo? Phase control?