We are planning to leave Syd around April-May 2012.

2 x adults plus a 4 year old and 1 year old (will be 2 by end of trip)

Will spend most of our time in UK with likely side trips to Europe that we can arrange from there.

Pretty flexible with other destinations. Open to advice re costing advantages especially if it means we can go up to premium economy or even business class for not much more than the crazy Australian fare prices.

Kyoto could be nice on outward journey, especially if we can get there during cherry blossom season.

Italy or Greece en route could be good, but probably a huge hassle to connect.

Obviously London is key.

Return leg via USA, friends in San Fran/San Diego/Portland but also could be interested in Disneyworld/land, Yosemite, Arizona.

If possible, final leg in Tahiti or Hawaii or similar.

Thanks for any tips and suggestions!