Spring road trip - maybe Denver - San fRancisco and back (different route)?

[bredman11]

Aiming to spend 3 - 4 weeks on road trip. Pretty flexible, but from UK thought Denver (or SF) a good start point? Have visited LA and SoCal, Nevada (and death Valley) and LV to Southern Utah and Grand Canyon/N Arizona. Aim of this trip is to see a bit more of the Western/Northern states, particularly interesting small towns and ideally with great scenery in between! Could start in San Fran, and finish in Denver? Or open to other ideas which achieve much the same thing. Enjoy meeting people particularly the kind you bump into in small towns or inns/hotels

Have had recommended: Denver, Buffalo, Cody, Elko, Yellowstone and Tahoe, and SF in the north; and pikes Peak, Moab, Canyonlands to Yosemite and SF via the more southerly route.

Any thoughts or inputs?