I'll second on visiting Maroon Bells although it has a special meaning for me as I climbed North Maroon peak in the mid 90's. That climb is very much mountaineering so not suggesting it for a hike. Although, that area near the Bells is absolutely beautiful and a nice hike from the bus drop-off, which is close to Maroon Lake, continue hiking up to the base of the Bells at Crater Lake. you would not be disappointed.
Near that area are cool little towns, Basalt, El Jebel, Carbondale where you can find RV parks nearby and some GREAT fly fishing. Although I've not been there, Marble and Redstone are nearby and generally highly recommended. Although Glenwood Springs would be on the larger side of these towns, it is worth the visit to go soak in the Glenwood Hot Springs pool.
Another amazing area in CO that shouldn't be missed.