We're in the faction for the exact same reasons you listed as 1 through 5. And a few more. The term closed economy is not precise, because you can get credits out, just not in. It is a reliable source of income. We dislike powermongering corporate profiteers the same way. And we sure like a challenge (those who don't never make it in, actually).
And yes, we are a trading and mining faction. Our key is stealth.