@NOOBY, it's very hard to grief the road as a whole, only individual mini-milestones. Even in that case the owner just have to destroy the thing blocking it or just safely continue their travel on the next mini-milestones. The main thing is, factions shouldn't have enemies willing to destroy the road in order to have it destroyed; there should be something that simulates nature claiming the road back. After all, personal claims and villages also suffer from this decay if there hasn't been a sign of life, so why not applying it to roads too?
Haven is a survival game, and I don't see how warping from one way to the other contributes to give it this survival feeling. Travelling far away without roads is indeed boring and it should be so in order to make people think whether they really need to get far away. As it is implemented right now, distance is an obstacle felt only by new players as the world is pratically globalized for the advanced ones. The concept of "far" and "close" in Haven, just like in today's real life, gets very blurry because distance is measured mostly in terms of travel time and not actual kilometers.