A fairly soft clone of the shatterloop trading engine:
Province/city/shop type layout is almost identical, with the caveat that locations are text based rather than graphical grid based. Maybe some different trade route types and more random properties as well. As well as varied province connections.
Items are also almost identical, though there's more variety and no shatterloop-specific materials.
Six currencies based roughly around the 6 shatterloop elements and tetrad stuff that dictates trading sequences.
A progressive delivery quest system similar to that of Courier -- you get increasingly better delivery contacts as you get more street cred with a delivery group. These will eventually result in going to different provinces.
This is needed so you can make money outside of the trading mechanic.
The end goal is to make some absurd amount of money, which requires making a trade with a specialized shop type where there's one per province and the range of value is pretty high.
Getting the capital for this requires doing the trading game in successively higher tiers, which itself ultimately requires courier work.
To cut down on the grind, you can make upgrades that either allow different types of scanning or different types of portals that allow you to move around more easily.
Additionally, shops should only allow you to buy exactly one of the item type you're buying -- this forces you to continuously make trades. This applies to the super shop as well, which only has one item available and the amount of profit required is more than one super trade.