The market is too simple. The choices are binary too often and that removes both the tension and the interest.. They need to be at least trinary and preferably well salted with quadratic or better.
– Train rush in the wharves. Implement the wharves as an ordered card deck. Only the top wharf may be bought. Some are upgrades/extensions to the current wharf, some are replacements. Periodically the purchase of a bigger wharf will result in knock on effects:
a) More goods enter the supply.
b) More goods are added to all approaching ships.
c) Sufficiently small wharves either rust instantly (are discarded from play) or last only to the end of the current stock round. (I like rusting better but it may provide too much of a run-away leader)
d) If a wharf rusts while it contains a ship with goods, the goods are discarded to the bank (or supply?) and the market price moved down as if they were sold(?)
– Ship capacity now affects the wharves they may dock at. If a ship’s contents are too large for the wharf a player brings it to, then ship must discard trade goods until it fits (this can be explained in terms of draught). Such discarded goods are dumped in the bank (or back in supply?) and the market prices are reduced as if they were sold(?)
– Players start with a pilot marker. During stock rounds they place the pilot marker on any ship which will arrive in the next operating round, or may move it among approaching ships (once). In this way players may place a partial claim on approaching ships.
– Some larger wharves come with additional pilot markers. Some are constrained to the next turn, two turns out etc.
– Players may bring ships with other’s pilots to their wharves.
– When a player buys a good from a ship with another player’s pilot or moves from their warf to their warehouse, half the value of the good must be paid to the owner of the pilot.
– When a ship empties during a stock round any pilot marker on it is returned to the owning player, who may then place it on an approaching ship instead of buying goods/wharves/warehouses etc.