There are better options than US 83.
Just because it is a number and a red line doesn't mean you have to ride it.
In Kansas, Hwy 23 roughly parallels US 83 to the east and has far less traffic.
In Nebraska, Hwy 97 parallels US 83 through the Sandhills and is magical.
If you can have completely empty roads to ride in the Great Plains, why not use them?
Also, US 83 has a disproportionate percentage of truck trafffic - bull racks, heavy ag.