As our National Parks are overwhelmed by an escalating number of visitors, threatening the ecosystems that the Parks were created to protect, it seems best to focus on establishing more National Wildlife Refuges; these wild tracts are generally ignored by most Americans and International visitors.
Set aside to protect vital habitat for both resident and migrant wildlife, most of these refuges offer limited human amenities; a visitor center and restrooms are usually the max. After all, they are preserved for the wildlife, not for tourists. Almost 600 are currently spaced across the country but there is, in my opinion, always room for more. Arapaho National Wildlife Refuge, in Colorado's North Park, is pictured below.
Many of these fabulous refuges, with their beautiful landscapes and abundant wildlife, would easily qualify to be National Parks but that would signal their demise. Paved roads and tourist facilities would be constructed, hordes of human visitors would arrive, the tranquility would vanish and the wildlife would depart for less disturbed habitat (while it remains).