Excellent post as always, @Stranger_On_A_Train , though focusing largely on the logistics of space mining. But I think one of the points that @LSLGuy raised that “Ceres to Earth orbit is as hard or harder than dumping Earth garbage into the Sun” is not correct; it seems to me that the most important criterion for the energy required to travel between solar orbits is the sun’s gravitational differential at the two orbits and consequently how different the orbital speeds are. IOW, sending a given mass to the asteroid belt (or back) is, in terms of energy requirements, a much lesser deal than trying to send something into the sun.
One can see this by comparing the Parker Solar Probe with missions heading toward the outer solar system. The Parker Solar Probe launch mass was 685 kg. Despite its relatively small mass, it required a Delta IV Heavy launch vehicle to help send it close to the sun, along with multiple flybys of Venus to further slow it down. The Delta IV Heavy, with a mass of 733,000 kg, was the world’s third-highest capacity launch vehicle at the time. Yet despite all this energy to slow it down plus the Venus flybys, the enormous potential energy from the earth’s high orbit will, by around the end of the year, give it an orbital speed of 692,000 km/h as it spirals closer to the sun, making it the fastest manmade object ever made.
The overall Curiosity spacecraft, OTOH, had a total mass of 3,893 kg. Despite being nearly six times more massive than the Parker probe, it was launched to Mars on a much smaller Atlas V-541 weighing just 531,000 kg.