I think it'd be cool if we could either get paid to supply engineered modules, somehow, or source stuff for other players.
Trouble is, that leads to all the malarkey regarding auctions and "gold-selling".
Still think it'd be cool if there was, at least, a weekly "galnet auction" where players could put unwanted ships, modules and mat's up for sale.
It'd have to be implemented very carefully, though, to avoid encouraging gold-selling.
Set it up so that you just deliver anything you want to auction to a station, store it there, and then anybody can participate in the auction from any station in the galaxy.
You bid on stuff, a bit like space-ebay, and then, at the end of the auction, you hand over credits and the stuff you've won gets transferred to the station you're at.
If an item goes unsold, the owner can collect it from where they stored it OR they can leave it in for the next auction.
And, yes. I'd include Cobra 4s, faction-locked ships, powerplay modules, guardian modules/SLFs, engineered modules and engineering mat's in the auctions.
If players want to buy stuff that they haven't "unlocked" for inflated prices, and other players want to earn credits by gathering/buying/building this stuff, good luck to 'em.
It's not like there's any "god-mode" items in the game which fundamentally unbalance it.