now I just need one more Supercharger between Richmond and Burlington, NC to get to Charlotte. I'm not sure i want to do that 200 mile trip in my 60.
By Google Maps, it's only 183 miles, which seems like a reasonable buffer, but I'm not sure what you've found real-world...?
Swinging by Rocky Mount to Supercharge adds 43 miles to the total trip, but makes your longest leg 128 miles. I don't know if it's worth the trade-off or not, and there is time of day and Raleigh-Durham traffic to consider.