I'm glad you liked it! I'm planning to work on this one a bit more over the next few months and adding one or two more destinations is definitely something I'm planning to do. The prices not going up can be a bit tricky, and it probably doesn't help that I don't fully explain it.
Each station has preferred goods and so the price is more likely to rise on those versus the ones that aren't. However, when you deliver goods the price only goes down. So if you deliver a mix cargo of the top 3 items, there is a chance those 3 will all go down and the bottom two won't go up. I probably made the variable prices a little too complex honestly.