I was absolutely gobsmacked by this building (and to an extent Martin Place in general) when up there last:
Interestingly enough Tays, the Melbourne MLC was identical to Sydney's and located on the corner of Collins and Elizabeth streets. It was demolished in the 1970s to make way for a larger curved MLC tower (Anyone have photo of that one).
Yes, Martin Place is like an oasis in a concrete jungle. My favourite parts of Sydney is the area around Hyde Park.
I think that Sydney has many more fine art-deco buildings than Melbourne, but I personally am not the biggest fan of deco, and most American cities have an abundance of it.
As a city, I prefer Newcastle in the Hunter Valley. It is like a mini-Sydney, with a flavour of its own and very much less rushed and cramped.