The Cassius hwy is much better than the alcan if you are looking to continue the Alaska experience. The northern half is narrow some what rough but little traffic. On a roughness scale I would put the Tok beaver creak run at 1 most severe, chicken at 3 severe, parts of Glenallen at 5 somewhat rough,Cassius at 6 somewhat rough, south end of alcan at 8 good.
I favor the road less traveled, Cassius. Drop down to the Canada border on hwy 97 and you are in for a treat with the fruit orchards in Canada and northern Washington.
Pops