Since there are very few rural areas that are not connecting points for other more populous areas, then perhaps it would be wise to legislate that one area of road in a rural place needs to have at least two or four highway type lanes. There could still be other small roads going through the town.
Anyone who would suggest this does not realize that the reason rural areas are still rural is that they simply do not have the traffic level that would justify such a change. Most truly rural areas can get by with just regular old two lane roads and this does not even come close to inconveniencing anyone who really needs to use them. Tourism aside, most people who use rural roads would think this idea absurd.
People who live in rural areas still drive cars and need to have the ability to have mobility, I think it would be a great inconvenience to them to get rid of roads and put in mass transit lanes and tracks not to mention the amount of money it would cost communities to undergo a project like this.
No, I do not think that rural areas should be required by law to replace roads with mass transit lanes and track and should be left as is. I think that they can maintain the rural roads at a much cheaper cost than going through a whole new infrastructure project.
No, this would be a really bad thing to try to do in this nation. I think that the way that the road system is set up today is a really good network, and that the only problems that come are in the big cities, where traffic is a lot worse.
Though, yes, many a rural area leads to more populous areas, many of those already have the necessary road conditions to make reasonable the use of roads in the area. If not, well, clearly the rural area can handle the situation. Only when it becomes best for the good of the area will bigger roads be put in. A mandate of "Just in case" is not necessary. Part of the charm of rural areas is that they are, in fact, rural.
Keep rural areas as rural as you possibly can. I do not think anyone would approve of the urbanization or suburbanization of rural areas. This would be like ripping sky scrapers down just to build horse farms. It's a riiculous idea, and people should stop proposing such nonsense so regularly.