While I wouldn't say i would never go back, I would not try and do the working visa bit again. The reality is:
- Everyone has the same idea and there is loads of competition for work and the employers know this.
- Going daily to job agencies to see if they had any vacancies that only seemed to offer manual labour/catering/charity work to holiday visa holders, any job deemed "good" was reserved for people staying longer.
- The hostels vary massively, do your research first before booking.
- Everything is expensive. We were surprised by the cost of living (food/drink) and ended up eating alot of fastfood to keep expenses down. Some days living off just super-noodles and boxed wine.
I went with 2 mates and we started in Perth as we knew a mutual friend there who got us sorted with a postal address, sim-cards etc then after struggling to find any work we flew to Sydney and ended up in Townsville on a farm. The heat, the backbreaking fruit picking, the spiders.... nah.
Made some great memories but could have achieved most of it by just being tourists and staying in hostels.