Finally booking our Australian holiday!

[Pinkybike]

Hi,
We are finally booking our trip to the east coast of Australia for next August.
There will be eight of us including three teenagers.
Im looking at large holiday houses and have already booked near Cairns.
We are then looking at staying at Noosa, Broadbeach or Goldcoast area.
Noosa is quite expensive, I’ve found a nice looking house on the Gold Coast but am not sure if it’s going to be too full of back packers, students etc.
Can anyone advise me please?
We’re looking for somewhere with shopping, restaurants, beach, possibly theme parks but not wild nightlife!
thank you!