The ability to move roads closer together or further apart so I could place two factory's between them would make it much more space efficient which is necessary for large corporations.
To stop people and the AI tactically destroying roads to competitors factory's you could make it so you cant delete a road that something is connected too and the road always has to connect to another road at both ends, so you have to build the new road before deleting the old road, hence there will always be enough roads.