Elevated++ has a platform but, it does not work like I had hoped. Elevated++ is mainly for railroad or single line use (not a huge acres covered with a platform) but can be used in single width platforms for close to the edge access from below.
What would be nice is:
A user selectable height platform that trucks can drive under (height may limit which trucks can drive under) that the trucks can access buildings and storages built on the platforms in the middle of a large platform? This is kind of a cheat but allows building factories above ground saving the ground for other things. Maybe platforms over planted forests, farms etc... Yes, I know, trees & crops don't like shade but lets just ignore that detail. :)
Oh and be compatible with the No Pillars mod? The Elevated++ get really strange results when used with No Pillars.
Thanks for considering this idea.