Melbourne is my home town, So I will choose Melbourne over Perth.
my observations coming from a person who has lived in Perth and Melbourne.
Perth-
Perth is a nice city, good parks, great weather, good beaches that are not far drive from the city.
No Trams, so inner city Transport is hard, however Perth does have the CAT buses which are free and run certain loops around the CBD and surrounding suburbs.
Fremantle is a nice place, as is the Swan valley, the foreshore etc.
Perth lacks that entertainment buzz, I was only in perth for a work course and trying to find late night places open in the city is still near impossible especially on a monday night. However it has got better with the Casino upgrade, more theatres and inner city bars, slowly getting better.
Great place to live for a family However......
Cost of living is higher, everything is inflated, Steak and chips at the local pub $40, rents are quite high too.
Also the Isolation is a negative, unless you love taking holidays to asia, than its perfect as it can be more cheaper to go to bali than fly home to Sydney. There's nothing else to do unless you go "south" to the surf and wine region.
Bogans are in Perth you only have to take a trip through the Thornlie or Gosnells region, or to the "Saint Hotel" located at innaloo. There youll meet a new type of Bogan "CUB" Cashed up Bogan.
Football wise unless you support Fremantle or Eagles than youll struggle to find any news on other teams or watch games unless its a blockbuster Melbourne game.
Melbourne
Great City, Diversified Entertainment, so much to do and see, endless options
Big Sporting city, with AFL, NRL, Soccer, Ice Hockey, Netball, etc etc
Great Transport, Trams, Trains, Buses.
You can go east,west, south or North and find Tourist areas to venture out it in, like Yarra Valley, Goldifelds Region, Great Ocean Road, Philip Island.
Located on the east coast, so a short flight to any other Capital city.
Housing and rent is reasonable, depending on where you want to live ofcourse.
I live in Ascot Vale approx 6kms from the city centre and Pay $400pw for a 2x1 House, which I feel is reasonable for location.
Weather wise, Yes Melbourne does has bad weather sometimes, and even in Summer some days feel like Autumn.
Finding a good beach is a few hours Drive, unlike Perth.
but thats all I can really Fault about Melbourne
It all depends on your Current Situation.
Im a single 30yo so Melbourne suited me way more than Perth ever did, just for entertainment and Sporting reasons, but If I had a family, I would be happy to live in Either.
Just my 2cents