Shipping Template

Is there any way to get more options for delivery times on the shipping template page? The drop down menu jumps from 2-4 days to 5-8 days for all regions. Ideally, I would set this at 3-5 days or 4-6 days. My options for my home state are more granular than any of my regional templates. I also experimented with other single state templates, but they lacked the 3 or 4 day sweet spot I was hoping to select.