I like the idea, it would be nice when barter skill will allow to get buisnes informations and trade between cities, like in good pirateslike games (specialy Unchearted Waters 2, anybody played this brilliant game?). But only way to make it not destoring economy system is making it profitable for cities also. However it is really hard to perform.
The only idea I have is make crafting require special parts, like some "rare alloys", "turbo-magneto-something-shit" or uraniumlike ores. let say that Hub and Modoc produce food that you can sell in Broken hills and Redding (according to number of food they store), where they produce Uranium (according to amount of food they have in stock, they sell it for low or high price, and when somebody buy uranium there, food in their stock decrease). Redding can produce some other ore, don’t know, maybe platinum or titanium with the same mechanics. Then you can trade this, let say titanium, to San Francisco, where some NPC buys it and sells rare alloys that are needed to every top weapon and armor - 1 for metal armor mk. II, 1 for laser rifle, 1 for minigun, 2 for CA, 1 for CA mk II, 2 for BA, 2 for plasma, 1 for sniper rifle and maybe for 5mm ammo, 7.62 and 0.223 ammo. From titanium or other ore, SF can also produce some "turbo-magneto-something-shit" which you can sell in Hub, NCR and Vault City, for money they get from food and other city activities. If you could buy implants, about which I wrote in other post, you can sell this shit in NCR and Vault City for money they get from implants selling. Maybe Hub and Modoc can buy brahmins while Broken Hills and Redding slave that also are needed to produce food and ores? It also can be possible to buy regular ores in Redding and Broken Hills or even alloys and metal parts, that they produce form slaves?
Maybe this trading system can be combined somehow with caravans. Players can go for themselves with goods, or with caravan, that city organizes, when they have really big amount of stored goods.
This way crafters, gangs and PvP players by buying resources (and eventually buying implants) will provide money for trading system, that other players can work in.
However, the BH and Redding, would be rather dangerous stops in traders trips...
Then with barter skill you will get better prices and info about current prices in other cities (with chance of success with cooldown or accuracy depending on barter skill). The prices will depend on amount of resources, that city buys in stock, and those resources will disapear in number according to quantity of bought goods, when someone buys them. So, you sell food to BH, and Uranium price decreases, while when you buy uranium, the food number in their stock decrease, so the uranium and food prices go high. However food should be particulary cheap to make it profitable for players.
With inflation system, about which I wrote in other post, cities will have another source of money.
Damn, quite new economy system!
What you think?