Nothing bad about cabbage hill except its a long climb. Trucks do it all the time.
Now, if you really want to avoid freeways, take US26 over MtHood connecting with US97 south at Madras. Just south of LaPine take 31 SE toward Lakeview. Or contunie south on 97 and at KlamathFalls head SE to Alturus,CA where you pick up 395 into Reno. 395 will take you down the east side of the Sierras. Be aware though this time of year anywhere east of the Cascades can be cold overnites. Most campgrounds will be closed or very limited service.
