I recently came to Karachi from Islamabad
So
here is the route we took
From Islamabad we started our joourney around 10pm
Reached Lahore, stayed there for the night
then next day was Friday and father had some work to do
So we started our journey from Lahore after friday prayer around 3.30pm
then next stop was Multan
we reached Multan around 9:30pm
stopped there
Then the Third day we started our jourey around 11am and reached Sukkher around 4.30pm
then stayed the night there
Then from Sukkher we started around 11am and reached Karachi around 6pm
we used N5 throught out the journey
From Hyderabad we took the bypass
About road condition
From Islamabad to the end of punjab road condition is good
As soon as u enter sindh you will feel a change in temp and also road condition
there is a patch of around 15 - 20km which is in bad condition
After Sukkher the road condition is good till Karachi