As an Australian, living in Melbourne ( under pretty severe COVID-19 restrictions right now .... ) I've a few comments.
It Is a long way to fly from North America to Australia - but it's the same distance for me to go to US. Would I go to North America for a 10 day trip - absolutely. Is it easier to do this business/ premium economy - absolutely. But I would be thinking in terms of 10 days from arrival in North America to departure., not 10 days from leaving home to getting back.
I plan o the basis that every day of inter-city travel is not being really part of a holiday trip, also day of arrival and departure.
Let's say you were in mid- USA, flying from your home to a hub, arriving LAX in time for customs formalities and late night departure. 14 or so hours later you arrive in Sydney, 2 hours customs/ baggage/ immigration, 1 hour to hotel. Check in, shower ( you will need it. ). Don't know about you, but after around 24 hours on the road, and around half day time zone change - the only place I'm going is to bed.
Re driving between major cities in Australia. Just don't do it unless there are specific things you want to see, and then add a second day.
As an example for Adelaide- Melbourne my family allows 10 hours, Melbourne- Sydney 12 hours, these are two driver, very early morning departure, good conditions, toilet fuel and fast food stops only times. We have state based automobile associations, Queensland one has a good free travel planner here:-
https://www.racq.com.au/travel/trip-planner
Unfortunately I don't think we will be going anywhere outside Australia until 12 months after a vaccine becomes not only available but pretty much rolled out both here and wherever we are going. Same will apply to receiving overseas travellers in significant numbers. Personally I don't think there is going to be a vaccine by 2 November 2020 ........
As to Australian travel right now - we have in total 8 states and territories, and pretty much hard borders in place between them right now. Essentially no overseas travel, a quota for Australians retuning from overseas, and two weeks mandatory quarantine on arrival. Even our most senior politicians have to self-isolate if travelling from Victoria to our national capital (Canberra).
Our travel industry will eventually open up, but one budget arm of major airline has folded, Virgin Australia effectively went bust. I fear the days of cheap local airfares are gone for a decade..