For medium distance transportation, it seems to me that buses have a lot of advantages, the biggest that there already exists a huge network of roads, in stark contrast to rail. They also carry a lot of passengers for the energy they use. However, having commuted for years by bus, the suspensions are ridiculous. It seems to me that there should be a private/public project to greatly improve bus comfort, which to me means better suspensions. Fully active suspensions would be a likely prospect.