I have done that and the coastal route. If going inland, try Tamworth to Goondiwindi rather than the way you suggested. It will save a lot of extra miles.
I prefer the coastal route. Wagga, Camden, no tiger country, through the VFR route between Bankstown and Richmond then pick up the coast. Williamtown isn't as bad as Dick Smith wants people to believe. In addition to the main ports, Taree, Port Macquarie, Coffs Harbour and others, there are numerous ALA along the coast, some quite large running skydiving operations. Fuel is readily available.
As you approach Evans Head, give BN centre a call, check the status or the restricted areas and let them know you'll want to transit the Gold Coast zone coastal. They'll probably give you a code and let Gold Coast tower you're coming.
You'll need to go east of BN zone via the Stradbroke Island.
If coming back, one coastal and one inland route. All you need to do then is decide who gets the best look at Surfers Paradise, you or the passenger.