I would also suggest the Buena Vista area and a drive up to the "ghost towns" of Vicksburg and Winfield (up toward the highway to Aspen from Buena Vista.) Aspen and the Maroon Bells are also good possibilities.
Another is to go on over to Gunnison (over Cottonwood pass) then up to Crested Butte. A good drive in that area would be up Ohio Creek road to Crested Butte--some of the best foliage viewing anywhere.
Oh, places to stay: we like Arrowhead Point Campground north of Buena Vista, but there is also a good KOA out south of town (Johnson Village), and several other good RV parks right in town.
There are several good RV parks in Gunnison including Tall Texan (out on the Crested Butte highway), Mesa RV Resort (west of town), and the KOA. We usually stay in the Tall Texan.
Either Buena Vista or Gunnison would be a good base camp for the RV as there are several good choices in both places, and there are multiple good day trips with the auto (or pickup if you RV is a fifth-wheel.)