I am about to post a article on this along with other topics.
if the black market was represented by pirates in the beginning of the game and disappeared when the pirates are wiped out. Pirates would spawn like everyone else to start the game, just to be clear. Would that be okay, that way there is no long term dependence and the game moves on...if you want.
DARCA
I hadn't considered the black market concept ... thats additional programing and an entire faction design no doubt.
To me ship building and controlling ship spamming is the main goal. Buy adding assembly tech to the research tree, ships can only be built at the speed of tech level, not economic wealth. Wealth would be measured in resources and cash to buy them, but ships can only be produced so fast regardless.
Also, manufacturing really is a split technology. Assembly and resource production being split changes the colony management concept.
Do you go for assembly tech and economy and simply purchase resources... Do you go for resourse production and assembly , then sell your excess ....
It adds a new layer of stradegy.
Also, using resource starving is a legit way to attack an enemy, it is happening today irl.