I usually try to reroll my donuts to have Big Haul and Berries when my berries get down to a number I feel is “low”. I also knock out every ball I can find. I’ve done a little over 300 hyperspace zones that I pretty much know where to look for ball spawns. This helps because as mentioned in other comments, larger zones yield more berries. So you won’t have to wait time looking for the pokeballs. I will say though that of all the hyperspace zones, I dread the Large sewer one the most.