I had in mind an image for each product. As the game progresses the products displayed could be more elaborate, colorful, or interesting in some way (e.g., gems and so forth). This would be an incentive to make progress in the game.
Another incentive is to let the player choose to specialize in specific kinds of products — e.g., a player could choose to trade mainly in food, or livestock, or minerals, or crafts, etc. I mention this because my own games tend to have one, and only one, path to the finish line. I think games that let players make consequential decisions are more appealing. It gives the player a chance to add their own "style" to the game.
Just my 2 cents! Anyway, I think your game has a lot of potential.
