I95 to I 81 north from Savannah

There really isn't a better option on I-26 to I-77 if you prefer interstates. The only other practical option would be as jaycocamprs mentioned of staying on I-26 to I-77. Problem with this route is you add a lot of miles (about 100), add Saluda Grade (6% for 3 miles) and still have to climb over the mountain with climb which is just as bad as the one on I-77 at the VA state line.

Only other option would include a lot of I95 which would be much worse because of the traffic.