Outta Vegas I'd head north through Zion and then continue on to the North rim of the Canyon. Zion is beyond cool compared to the grand canyon in my opinion.

 

thanks for the good advice. I will diffidently use some of it.

 

Yosemite- Go via US395, Tioga Pass to the Valley and backtrack back out to Lee Vining.
To Carson City, take the detour to Bodie (20 mi north of Lee Vining)- Cool spot
From Reno, take I 80 until you get to CA 20 (20 mi west of Donner Summit) and stay on it all the way to US101. You can take the Old Road US40 (2 laner), from Truckee over Donner (great view) which kinda parallels I80. It ends (exit 1610 right as CA20 starts (exit 164)
Stay on US101 until at least Newport. From there north, most big towns (there aren't many) have a route to Portland.
From Portland take either the Old US30 through the Gorge or take WA14 on the north side to Hood River. Go on OR35 south to Mt Hood. Use US26 all the way across the state.