[tedmiston]

And here is some aggregated data from Nomad List that might help you compare short to medium-term living in Melbourne vs. Sydney.

                           | Melbourne | Sydney
    ---------------------- | --------- | ------
    Internet               | bad       | bad
    Fun                    | good      | great
    Nightlife              | good      | bad
    Free WiFi in city      | bad       | great
    Places to work from    | okay      | good
    A/C or heating         | great     | great
    Cost of living         | okay      | bad
    Quality of life        | good      | good
    Safety                 | good      | good
    Friendly to foreigners | good      | great
    English speaking       | great     | great
    Racial tolerance       | good      | good
    Female Friendly        | great     | good
    Gay Friendly           | good      | great

Admittedly the qualitative scale is subjective, but it is based on individual responses.

https://nomadlist.com/melbourne-australia/scores

https://nomadlist.com/sydney-australia/scores