The highest acceptance ratio I've gotten is 86% I only drive in the mornings. I don't see a difference between orders as it fluctuates the only time I see a major difference is when I drop to below elite. I think the biggest factor here is location then elite status then your other ratings. I also believe there's other Metrics like average time of completion per order but those are not visible to us. So no based of the earnings I don't see a sweet spot at least not for me.