The roads that you are referring to, already exist on Iranian side:
List of highways in Iran - Wikipedia, the free encyclopedia
It is on Pakistan's side that things are quite bleak. I have seen these roads so I know. The infrastructure on Iran's side is in MUCH MUCH better shape than on Pakistan's side. On Pakistan's side of the border, actually there is no electricity grid either, forget about proper roads. You realize the difference in situation on border crossing itself. On Iran's side, there is a proper building for custom and immigration surrounded by a complex with proper internal roads, concrete ground etc.
On Pakistan's side, I was shocked that there was a mud room where custom and immigration was being handled. The ground was mud, and no complex existed so passengers were basically on their own on the mud. Even the electricity for Pakistan's immigration and custom was the courtesy of Iranian side. The immigration officer on Pakistani side though was very chatty and friendly and joked with me, showing me his stamp with which he was stamping the passports (he let me handle it, which was quite heavy, about a kg). He said the stamp is itself an antique, about 5 decades old. It had a wooden handle with the stamp itself being of a metal construction with engravings on it. I had never seen one like it before. It was from another era. And it was the only equipment they had, along with old paper registers and a pen. On Iran's side everything was computerized.
