I use to fly a route that took me from Redcliffe - Maleny - Lake Cootharaba - Noosa - Caloundra and back to Redcliffe. Took me about an hour in a 172. Friends loved it. ATC will probably keep you over water from Noosa to Caloundra so the person in the right hand seat gets a good view as well.
If you have a bit more time ($$$) you can also head over to Moreton Island and down to Notrth Straddie or do a lap of the Glasshouse Mountains.
There's plenty to see and great weather for flying at the moment.