Why the Refiner comes first
The workshop looks like six independent tracks, but they're chained together by materials. Higher-tier upgrades on every bench call for advanced components, and those are produced at the Refiner — it turns the mountains of common scrap you already haul home into the rare inputs the other benches need. Rush the Refiner and the rest of the workshop stops gating you on rare loot; leave it late and you'll grind dangerous zones for materials you could simply have crafted. That single dependency is the reason a smart upgrade order beats brute-forcing benches in the wrong sequence.