Auto-Adjust Import Priorty Based On Storage Threshold

When an input priority is set, trucks will obsess over maintaining the requested fullness of a storage container to the detriment of anything else with a lower priority. It would be nice if the priority were adjustable based upon how full the storage container is; Priority for when container is x% full, and another priority for when it is y% full.
This way storages can be filled and allowed to settle for a bit while other storages get deliveries.