Enough of this offensive nonsense.
Your argument is fundamentally flawed, amongst other things. Australia is a country of approximately 20 million people. It is a multi-cultural country. Indigenous Australians (aborigines & Torres Strait Islanders) are estimated to make up 1% of that population. A large proportion of the population has no cultural connection with England or, indeed, the United Kingdom. They, or their forbears, have come from Africa, Europe, the Mediterranean, the middle east, Asia, America (and the list goes on).
If, for one moment, your flawed proposition were correct, (that Australia is most made up of English migrants who should return immediately) just pause to think about the obvious outcome; the collapse of a nation State (Australia) and an almost unbearable burden on another nation (U.K.) due to the influx of some 19 million people. Let's also pause for a moment to think about the effect on other countries, such as the U.S, who are major trading partners with Australia.
Oh and lets not forget another aspect of social dislocation -> many non-indigenous Australians are married to indigenous Australians. I assume that you propose the immediate dissolution of those relationships? Even if those relationships were exempted from your crazy plan, that would not be enough to prevent the collapse of a nation and the human misery that follows. Oh, and I also assume you've consulted indigenous Australians before recommending your 'ethnic cleansing' of Australia?
No, I do not think you are funny. No, I do not think what you keep proposing is a 'joke'. Just the way the forced dislocation of many nationalities/ethnicities in Europe during 1939 - 1945 was not a joke.
I normally do not respond to misconceived opinions but your ramblings are more than an exercise of freedom of speech. They are bigoted and dangerous. Please stop. Also, for obvious reasons, please do not send me another friendship request.