Absolutly nothing wrong with a Pakistani citizen marrying an overseas Pakistani from any part of the world. As long as it is for legitimate reasons and not to abuse the nation's immigration policy or visa of their chosen spouse. This only brings Shame onto the wider Pakistani diaspora. My own relatives who are British Pakistanis, born and raised in the UK have married citizens from Pakistan. Regarding a Pakistani marrying a non Pakistani? My only opinion would be both must be Muslim, that is if the Pakistani is a muslim as Pakistan also has Hindus, Sikhs, Christians etc. If a Pak Muslim marries a non Muslim I do.have strong objection to such unions. However if both are Muslim and one is from a different nation and culture, then entirely up to the individuals and I pray they both have a happy prosperous marriage.