If you can take the car to Gilgit, then you must take it ahead of as well.
I don't prefer traveling on such a long route in Ramazan.
Lahore Naran about 12 hours
Road condition - I haven't taken the route via babusar and hence can't comment.
Attractions are KKH itself......Indus river is the same but mountains change.....green, barren, soft, hard......
On this road I always carry 20 lit hioctane.
Make it 7 days at least.
If you both will drive, you can do it in 22 hours from Lahore. This was my travel time during this trip.