I would not recommend traveling on Daewoo or any other "luxury coach" with family especially if you are traveling with elderly or the younger ones. Even for the healthier lot, it is bit of a drag. You can only recline your seat a little provided the person sitting behind does not raise any objections. They do reach their destinations on time but the journey is quite uncomfortable and boring.
Train is better as you'll have greater comfort, access to toilet, sleeping arrangements etc. Try good trains like Tezgam which does not get as late as some others.
You can also try breaking your journey by traveling to Lahore or Multan by train and then taking Daewoo to ISB.
You'll only have to schedule your journey with some extra hours if you are traveling by train but it is not a big deal if you are traveling with family.