I think that the cargo runs both shows how stuff is done right and also have some mistakes.
I really like that you know what each thing is worth, instead of random numbers. Maybe reduce the gap between min and max value on other items?
I don't like the fact that you can do more voyages at once. It should count as a normal voyage. Also, when you can only do one (maybe multiple maps can appear out of the same one) the price of the cargo should raise just a little. It will be much because you take a lot of cargo at once.
