Have you considered putting Heavy Industry into the research system? I could definitely envision the same tiered approach, where you can end up with domain-era heavy industry; such as starting with default HI, then you have to research to get orbital works, then you have another tier(perhaps you need to sacrifice a corrupted nanoforge to research, or to build?) that's just Domain-Tech Orbital Works, and then a final Advanced Manufacturing Center(that might need a pristine nanoforge to research or build) or Advanced Shipyard(Same; but while one ups production of goods and thus income, the other improves local fleet size/quality and your custom production total), representing climbing back up to the peak of domain-era manufacturing ability.
Or possibly an integration with TASC; you can research essentially standalone versions of the heavy industry/refinery; a true 'orbital works' platform that handles large-scale manufacturing/refining and is built off on its own, a cramped(stuck at 4 max size market) facility with an enormous production bonus.