Just a thought.
1. The trucks would look more realistic.
2. Their would be escorting vehicles that would provide air cover.
3. Instead of just coming from a factory replace it with a small strat that would have: gas pads, troops barracks, ord bunkers and a few AAA emplacements.
If you destroy the supply area completely supplies would not be able to run into the gas. Destroy the gas pads, the convoys would not be able to go that far. Destroy the troops or ords, the base would take longer to resupply from the convoys.
