Sometimes, it's realizations like this that make me think Elite Dangerous is less a game about space travel than it is a 3D picture of space itself that you just happen to be able to travel through... I guess that's one way of achieving immersion!
Anyway, Victoria 3 will be out next year so all will be well
EDIT: To contribute more than snide remarks, I will say that I recognize it would be a difficult thing to replace the current economy with a fully simulated one; but I think even a partially-simulated one would do wonders for interactivity in this game.
My understanding of real life business/trade is that it is based primarily on exploiting differences in production prices among regions; so start with that. For every market in game, have it look at the supply/demand prices of every other market within a set distance; then local prices adjust based on how those other markets' prices move. That way, as players satisfy demand or deplete supply in one market, it spills over into the surrounding ones. You could then get creative with things like having missions/activities that create some kind of "Blockade" BGS state in a given system so that it affects its surrounding markets less; or another BGS state that states "due to increased security, local traders feel more confident venturing out to further makerts", increasing the range of markets considered for local pricing. Stuff like that.
On the backend, code-wise, this would probably end up being just a giant spreadsheet; so nothing revolutionary here, just a lot of work to get implemented in the first place and to balance. So if you want to start small and not upset the apple cart too much, you could start with just the small markets at each Odyssey settlements and then go from there.
I'm mostly a combat player, so there might be something about trading currently that I'm missing. Anybody have anything positive to say about how trade works right now that they want to share?