You seem to be asking three questions about this:
a. is there a lot of asphalt? Someone else might have the inclination to research how much sealed road, unsealed road and 'natural' path is involved. My memory of the CP and CI is that where the routes can be taken off-road, they are. The roads that are used are quieter ones in the main, but that doesn't mean that you won't have to walk beside a major road coming into a town or crossing a river.
b. is it urbanised? There are major towns and villages on both routes. Most of these are compact places, and don't dominate the countryside with an extensive urban sprawl. Even Santiago, which does seem to spread out more than some of the other cities along the routes, isn't that extensive geographically.
c. is it scenic? Yes and no. At one level, this region has had centuries of human intervention, and there is little that doesn't show the result of that. Some natural woodland does remain, but you are more likely to be walking through farmland or forest plantation. You will still see the natural shape of the landscape - the topography of the land, and in short sections, the coast. But don't expect any route to pass through any large section of the countryside that has remained in what might have been its original natural state.