Pakistan's central issue with India is Kashmir, not India's muslims - India can disengage Pakistan by solving Kashmir's issue. And your second deduction is faulty too, the three communities (PM, IM, BM) will grow apart more and more with the passage of time simply because of isolation.
That was impossible, the educated elite was predominantly Muhajirs and Punjabis, even in the 1960s 34.5% of civil servants were Muahjirs. Nations build upon modern educated and hard working populace, not some pseudo- historical racist bullshit, otherwise your greater Khorasan "non- Indic" countries like Tajkistan , Afghanistan, Uzbekistan would not have been corrupt and riddled with chaos.
That's one the dumbest argument I have listened in ages, lingua franca are not "chosen", they are spoken by the elites and adopted by the masses.
That's pseudo-historical bullshit, Buddhism and Hinduism too were dominant in present day Pakistan. IVC was spread from Indian Gujarat to NWFP. Hindu Shahis were ruling Afghnistan etc.
It's all about Kashmir, I don't know why you're willfully ignoring that
Nope, while the Yavanas (Greeks), Shakas (Scythians) were initially termed as mlechchas, they became Hinduised pretty quickly, ancient brahmins just wanted Vedas to be followed - when someone started doing Ashwamedha and rewarding brahmins, that would please brahmins, ancient Hinduism is not called Brahminism for no reason. Also it would be foolish to assume Sakas were limited to Pakistan, Western Satraps had their capital in Ujjain, yup in Central India. It is also reported that there was marital alliances between Indo-greeks and Mauryas, yup today's Bihar.