Well from the development Perpective isn’t it was the best so far? I am asking a question not arguing…
Ayub Khan created two units. One unit broke away and the provinces of the remaining unit still have huge resentments / differences specially with Punjab over projects like Kala Bagh Dam, Bassha or Munda Dams. CPEC created another issue by which we have witnessed separate demands from the provinces. If you look at the cause, you will find that during the time of one unit, every person from West Pakistan was bound to visit Lahore (being capital of West Pakistan) even for SSC or HSSC board exams because there was only Lahore board in West Pakistan.
Visitors from far-flung less developed areas with deep sense of inferiority complex whenever had to visit Lahore for their official business became prime target of Shuggliaa style Juggats of Lahories like... "Oye Khan Saab, Kia baat karta hay...Tumharay Maghaz (brain) may Watta hay". Such way of dealing created deep divisions from which Pakistan still cannot recover fully.
I remember when Shams ul Haq (Former Chairman of WAPDA) was advocating Kala Bagh Dam on national television, when he said that let us create just a reservoir to store flood water of Indus river which shall be released slowly back when the water shall be required in Autumn...i still cannot forget the answer of one Sindhi nationalist..."Okay so you wanna raise up the underground water level of Punjab with this reservoir, than Punjab must also release their underground water via pipelines in Indus too...!!!!!" You can just imagine the division/barriers we have created. We need an original workable long-term fruitful economic development with the help of social scientists. That's only way to move forward.