I think Bokhara2 is probably meaning the New England Hwy. There are some cute towns along the way, Tamworth (country music capital) and Armidale. Tenterfield is where Peter Allen was born (you might know the song Tenterfield saddler).

Avoid the Newell Hwy, it's the main truck route between Brisbane and Melbourne and full of B-doubles.

The Pacific Hwy is the coast road. It might make sense to drive both ways, you'd avoid any drop off or one way fees. I'm almost certain it would be cheaper to fly (fuel is expensive here), however, you'd miss a lot of scenery and walks.