Big shipments VS small

so far ive been sending out multiple small shipments per day and never really gotten anything except an occasional divine. is it better to save up and send out 1-2 big shipments per week? would the rewards be much better? i saw some guy post his rewards after he sent out 50 mil shipments. he had multiple divines and 4 mirror shards. was it just rng or thats how rewards look after you save up your crops all week?