Hey there, I just did that (route 2) this past November thru December, stopping along the way. Not a bad route and does cut off a lot of the mountain passes. The Blythe up to Vegas road is mostly a 2 lane road, but not bad. I did that portion on Thanksgiving Day so traffic wasn't an issue. Instead of going around Vegas and Salt Lake City, I did just stay on the interstate and avoided rush hour, not bad.
good luck and have fun..
1996 Newmar Mountain Aire. 3760 CA
2006 to 2015 Boxer named Cash (aka Cassius Clay)
2016 - Boxer named Chevy