Official requirements of a cargo spacecraft for China's new space station. I don't have the time or technical grasp for a full translation, so I will summarize the points I do understand:
- 1000-4000kg carrying capacity going up.
- 100 - 300kg carrying capacity for return trips.
- Cargo craft is to carry waste and garbage on return trips.
- Enhanced location beacon for ease of locating the cargo craft once it lands on Earth.
- There will be 2-3 supply missions each year.
- From the time a re-supply order is issued to the time the cargo craft docks with the space station, the duration is not to exceed 45 days.
- Economical launch and operating costs, to be internationally competitive.
Just a minor clarification on your third bullet - garbage from the space station is to be de-orbited in a controlled manner and fully combusted on return to Earth’s atmosphere without residue debris.