Hi Dean
This is Sajjad, i am also kind of expat here, but was born here in Pakistan, therefore , not a stranger-- now a days I am based in Islamabad too, coming to your question, regarding your wife and baby, frankly i see here more Chinese among the expats, there are more expats from Asian side then whites here- however you have to choose an appropriate sector in Islamabad to enjoy more life here, and meet more expats while you working here. this is important. otherwise, Islamabad is a city of Scenic View, rich in nature and many expats. Islamabad being Capital of the country, is more organized and clean, you may find even local friends having similar taste and knowledge of cultures as probably any westerner know, but still better , respect the culture, in term of dressing and opinions about religion... you may find my tips on this forum separately for women and men
Enjoy your stay---- Cheers
S.Haider