Currently you can have an oil rig supply a circuit network amount for the amount of Oil its individual patch is worth as well as the greater patch near by. It would be nice to be able to supply the current amount of Oil in its buffer as well. If it was full, it would output the full 100k oil, etc.

The reason this would be useful is if there are multiple oil rigs nearby, it would be nice to be able to disable the associated port until the buffer was near full. That way, the tankers would maximize their trips. As it is, if the port is close to the rig, a tanker can end up ferrying very small amounts back and forth.

This functionality is also useful if you are using the LTN ports to have the port at the oil rig expose that they have enough crude oil available to qualify for being a stop.

EDIT: Just realized that this issue is similar to the "Logistic Train Network Integration Issues" discussion ( https://mods.factorio.com/mod/cargo-ships/discussion/6212b605d8c340652433236f ). It looks like the problem with implementing this functionality is that oil rigs are implemented as oversized water-only pumpjacks with a tremendous internal buffer, and internal buffers aren't natively able to expose their values to the circuit network.