Last summer, I took I-5 to the Oregon Coast and was pleasantly surprised that they had repaved some long stretches since I last drove on it. Wasn't a bad drive.
When I've taken 95 to the coast, I go 95 to Fallon, then 50/80/395/44/89 to I-5 by Mt Shasta.
Try this website:
www.flattestroute.com
Look at the graphs under the resulting map. If you pass your mouse pointer over the graph, it will pinpoint the position on the map.
2002 Itasca Suncruiser 32V
2012 Suzuki Grand Vitara