Well I ended up writing the core logic back in July, but then I was homeless for a few months so not much work got done on it since. As it is, you can make mining modules, send them up in a rocket, and ores will steadily accumulate in orbit until called down to an Asteroid Targeter, which uses it to spawn resource entities. At that point they're mined normally with a miner, so productivity applies.
Another advantage of this system over the old is that any (non-liquid, non-infinite, 1 tile) resource that spawns on a surface can be supported automatically. No more hand adding every resource.
Hasn't been balanced at all, techs exist but aren't placed/priced properly, no GUI so info only comes from /asteroid command, interfaces haven't been added for better cross-mod support, basically EVERYTHING needs new sprites, and a crap ton of testing still needs to be done, but it's technically playable.
The old method that 0.9 uses is still available - there's startup settings for basic and advanced mode, basic being the old and advanced being the new.
Now that things are settled again might get back into it and see about getting it polished enough for a release.