Hey Ali,
I have made the below itinerary and I think this would be perfect. Any further recommendations would be appreciated though. Sorry this is 1st time Im going so too many questions 
DAY 1. (ISB- Naran is almost 750Km) night rest in Naran
Day 2. Leave for Hunza early morning Visit Naltar valley and then night stay in Hunza.
Day 3. Visit Altit and Baltit fort, Eagles Nest and rakaposhi view point and Night stay in same hotel.
Day 4. Leave for Khunjrab early morning, visit attabad lake on the way, come back to Hunza Stay for the night. (I am thinking not to go Gilgit and stay in Hunza since it would already be a long journey to Khunjerab and back)
Day 5. leave for Skardu early morning. Will make it there by evening. Night stay in Skardu.
Day 6. Visit Shangrilla and Kachura lake as well as the cold desert then night stay in Skardu
Day 7. Leave For Deosai early in morning. sadpara lake will come in between. also visit Sheosar Lake in Deosai, make the trip long but worthy to visit rama meadows and view Nanga parbat and back to Skardu and night stay in Skardu.
Day 8. Leave for Shogran/ Naran stay a night.
Day 9. Leave for Islamabad.
I believe this is pretty viabale and also gives us enough rest so that we are not exhausted once we get and have to go to work after 2 days 