Secularism or no secularism, if your population is not ignorant and well-educated in general and in terms of Islam, the Islamic heritage will be reflected within the state and population through acts and evidence on the ground. A state is after all nothing more than a collection of individuals.
In KSA you can leave your house, cars etc. open and nobody will dare to steal or rob. Alcohol could become legal tomorrow (by the state) yet still almost everyone will refrain from drinking due to their Islamic upbringing.
There could be 1000 new restaurants serving pork, locals would still not buy it.
There are many so-called Islamic states out there that are only Islamic in name just like there are secular states out there that have better Islamic principles and more law and order than Islamic states.
Pakistan does not become less or more of a mess regardless what the regime/people in power decides to call itself.
If there is good it will be reflected by the people and if there are ills they will be reflected as well. As a collective the state of the overall society will be reflected in this way.