I am not a lawyer, but I am just about to finish law school, so should be in the next eighteen months at the outside, in Australia no less. But you still shouldn't trust me ;).
If the police are questioning you with the intent of using the information as evidence in court, they do warn you along the same lines as the Miranda rights. (in any case, Miranda was more about the fact of police having to inform about rights than the rights themselves.) You get two calls - one to family or a friend, and another to a lawyer. I don't know where you get the no-right-to-our-homes, and there's certainly a concept of illegal search, seizure and inadmissable illegally obtained evidence.
All true. The problem is none of these rights are constitutional. Whereas the government can never take away these rights in the US, thanks to the 4th amendment, they can be removed in Australia. All that's needed is for Parliament to pass a law. As we know, when it comes to law-and-order stuff, that's stupidly easy. All that's protecting us from tyranny is the goodwill of our leaders. That's why we need to complain about reform like this.
We might not have a Bill of Rights enshrined in the constitution, but we have 800 years of common law to draw on, given the courts recognise British court decisions as being relevant to Australian laws. Many of the rights you cry poor over have been ruled on in past legal cases.
Also true. But the rulings are always on the basis of interpreting legislation to be consistent with those rights where possible. We have supremacy of Parliament: if they pass a law changing the rules of evidence, the courts can't stop them. The big exception to this is political speech (and voting); these rights are guaranteed by the constitution. Limits on these can (and have been!) struck down by the courts: the Communist Party Case and just last year in Rowe v Electoral Commission. Search and seizure though are absolutely at the discretion of Parliament.
This supremacy of Parliament is why it's so important to be careful about who we elect, and to stop them from pulling shit like this.