Ok folks, you've not failed me yet! Here's one that may require some Canadian input. We're going from Vegas to the lower mainland in B.C. Not looking to sight see or doddle. What would be the easie...
Us93 north from LV to Idaho, I84 west to Oregon, I82 to I90 to I405, I5 to the border. Or even US97 to the border, and BC3 to the Lower Mainland - that avoids Seattle.