Your change actually slightly nerfs reprocessing asteroids, since in the base game you get on average 1/3 of each of the other two types per chunk consumed, but with your nerf it becomes about 0.28 of each. If you changed the amounts to a 10% chance of getting the same asteroid back and a 30% chance of each of the other types, then the ratio is restored and you get reprocessing back to base game effectiveness while having the same nerf on quality casinos. This change does make reprocessing slightly faster, but you could make the recipe slightly slower to compensate (which would nerf asteroids even more).
Feel free to take this idea or leave it, but your changes seem interesting and I might give this mod a try once I finish with my current run.
