The identity is of course Pakistani, not Muslim. Muslim is a religious characteristic.Its very important we become more authentic as a civilization and embrace our history in all its forms. It must be Pakistani the identity, not Muslim the identity. Pakistan is made up of many faiths and beliefs and ethnicities and backgrounds. Give them all an opportunity to become part of the identity.
The case study of Bangladesh is a classic example, Islam did not save Bangladesh from separating. Their cultural needs were not respected so no faith is not the glue that binds. Its already been debunked.
Objective should be to reduce the space of our two enemies, Indians who claim our history and Islamic extremists who do not accept Pakistan the nation state and geography. Go secular, embrace our history and watch in a couple of generations how Pakistan transforms into what it should have become.
Going secular at this stage is impossible, and the non-Muslims are a statistical minority in Pakistan, that's not to say they aren't Pakistani.
Bangladesh was a totally different matter and more political in nature.
The very foundation which Pakistan was created upon was a Muslim homeland, it is better as a semi-secular Muslim state which it is right now. It is a fact that Pakistan is the inheritor and beacon of South Asian Islamic history and civilisation.
But we need much better management of religious madrassas and institutions which I touched upon, who are controlled by uneducated extremists and a breeding ground for more intolerant extremists.
The national identity is also incorporating both non-Islamic history too like the IVC, Raja Porus, etc. There is plenty of room for non-Muslims to fit in due to this, especially due to the shared cultural affinity which will be present as they are the same people as us, and since we aren't a strict Shariah state nor will we be.
The idea of a secular Pakistan shouldn't be entertained as it simply denies the very basis of Pakistan's foundation, it would increase separatist insurgencies by 1000x.
We are a moderate Islamic society by nature. Semi-secular Muslim state.