Allow Train Beds early to help planning or other early assistance for train tracks.
One issue I often run into when starting a new game is planning for trains. It would be helpful if unlocking the crusher also unlocked a “train bed.” This would be the gravel foundation for tracks, made only with gravel, which could later be upgraded into full rails. Having this option would make it easier to plan layouts before trains become available.
Another possibility is to allow placement of “planning tracks” once the planning tool is unlocked. These would act as placeholders for future rail lines, letting you design the network in advance without being able to build or use the tracks yet.