To take full advantage of Intersection Marking Tool, you need blank roads. To cover them with ploppable asphalt is an alternative, but it's hard to achieve this with curves and slopes.
Blank Roads are needed, and I've made two sets, one with vanilla roads and one custom (working on a remake of this one).

I'm planning to do a blank version of the Two-Way Highway and National Road included in Mass Transit.

Any thoughts about this, and what other roads we need a blank edition of?