Looks like a great trip to me. Hope you have a most wonderful time.

1. I agree with Alan that this looks like a fine trip. I don't think you are trying to do too much.

2. For the Coastal Road portion of your trip, are you planning to drive from Melbourne, turn around and drive back to Melbourne? If so, I might suggest that you continue toward Adelaide instead of returning to Melbourne. We did this trip in reverse (Adelaide to Melbourne) a few years ago, taking 3 nights and 4 days. It was not a rushed trip at all. Also, once you get to Adelaide, you may want to go to Kangaroo Island in lieu of your proposed trip to Uluru (Ayers Rock).

3. I have been to Uluru twice and enjoyed it, but it's certainly not for everyone. It's probably the kind of place that deserves a visit only if you really, really want to go there. As you have mentioned, the prices and the logistics can be daunting. If you aren't "wow'ed" about what you have read about Uluru, maybe you should skip it, no matter what your friend, I, or anyone else says.

Hi
What time of year are you coming?

Agree with Longhorn about continuing on the Great Ocean Rd to Adelaide. Besides Kangaroo Island, you could drive north to the Flinders Ranges for a taste of the real Outback. Then fly to Sydney from Adelaide. The Flinders Ranges (e.g. Wilpena Pound) are very beautiful. You could also visit some of the beautiful wine country around Adelaide.

The other suggestion would be not to drive through to Adelaide, but to loop back to Melbourne through the Grampian Ranges. Not as "outbacky" but are highly regarded for scenery and wildlife.

I love the Red Center, but go only if you can make it worth your while by seeing some of the other sights like Kings Canyon and the Olgas. Especially if you drive up to the Flinders Ranges, you could bypass the red Center and say you've seen the Outback.

The Brisbane/Gold Coast area has a lot of natural beauty. Be sure to visit Lamington National Park while you're there.

For the Barrier Reef, I'd suggest somewhere near Cairns as your base (say Port Douglas), rather than Airlie Beach. In general more to do and see besides the Reef. And I'd spend more time up there if you can - maybe shave a day or two from your city visits.

@longhorn - thanks you definately have given me food for thought and some new ideas. Kangaroo sounds interesting.

@Judith - October

@Ralph - thanks for more information and ideas. You also have given me good food for thought and more to research.

This is a big trip and requires a lot of thought and planning, but you guys have helped me a lot.

Thanks!

In October the Flinders Ranges should be great. Lots of wonderful photographic opportunities and good walks. I particularly like the Brachina Gorge drive. Make sure you take the little extra walks if you have any interest in geological or biological prehistory.

The Wilpina Pound/ St Mary's Peak walk is wonderful. Be aware that this is one place where I found the walking times posted to be an accurate reflection of the time needed walking, so add on the time you need for sitting around, photography and eating lunch.

http://www.nationalparkguide.com.au/south-australia/flinders-ranges-national-park/

This time of year can be a bit windy or absolutely still so take that into account when planning your reef and water days. Flexibility is the key and as it is outside peak times it should be easy enough to do that. The Whitsundays are great http://www.tourismwhitsundays.com.au/ but I am biased in favour of north Queensland because of the hinterland. Not that there is nothing to do around Mackay and Proserpine, just much more on the Atherton Tablelands and points further west. http://www.athertoninformationcentre.com.au/itineraries.html
www.yungaburra.com
www.chillagoehub.com.au/
undara.com.au/
http://www.cairnsgreatbarrierreef.org.au/

I'd second the idea of Wilpena Pound if you have the time. It's such an interesting part of Australia . Picture red earth, many, many emus, wallabies and kangaroos, interesting abandoned houses/settlements, and the unique land form of the Pound itself. I really loved it and found October a fantastic time to visit, because there are few flies, beautiful warm afternoons but cool, even cold evenings. The light is magical, too.
Have a wonderful time in Australia!

And the stars...we still talk about the stars after our trip to the Flinders Ranges three years ago.