Hi Nat,
I came in 2005 with my DD, leaving DP behind for work and loved it as soon as I arrived.
I'm in Sydney, living on the beach, and the lifestyle is so much better than the London one I left behind.
Having a child has made such a difference, without DD I would probably have carried on globetrotting with work, but I know DD will have a great education here and grow up sporty and outdoorsy. She goes swimming at the beach every weekend, has amazing facilities at her school and loves the animals here - we go to wildlife parks all the time, play with the birds and wombats and cockatoos, kangaroos, wallabies - it's amazing.
The only problem really, as you say, is family. We budget for flying back, it's very expensive and also I miss the proximity of Europe - being able to fly to Paris or Milan - I would have enjoyed being able to do that with DD.
However, we webcam back to my parents, send lots of photos and with regards to travel, you can fly to fiji for a week for $600, inclding accommodation, so it's not all bad!
I miss London theatreland, but we go to the Opera House a lot, see theatre and ballet and sit on the harbour, which is amazingly beautiful and just gaze in wonder at the Opera House and the harbour bridge.
When I flew back to London in the summer I hated it. I hated the rudeness and the greyness and how crowded it was. I did however enjoy M&S and monsoon .