Cool - so is it py-asphalt that you would like turned into a road surface? If so then I can add this to the next release. I am in two minds as to if I should give an option to remove the transport drones road surfaces if there is an alternative provided. It could break some games if the mod-specific road surface isn't available until later than transport drones are unlocked.
I am not the scripting expert but it should be possible to run script when save is loaded and then upgrade new surfaces and by default enable them with technology. Is it possible?