I have seen the difference in the buildings myself and thought much the same,there still seems to be a lot of jobs posted in Brisbane for bricklayers and the prices are similar to Sydney although both less than half of the uk (not moving for the money)
I really would like to hear from some people doing it to find things out like how much time they loose with weather ect and how it works for them .
I did aim to do all this the last time I was in Australia on a working visa but met a women after 8 weeks fell in love and followed her back to Germany now 5 years a marriage and two kids we want to come back.