Yep - Australian citizens with Australian passports will be allowed in all of those countries you mentioned with no fuss at all. No electronic pre-clearance stuff to fill in.
Unless you were planning to seek gainful employment and/or stay more than 3 months...
Doubt it, however.
What is even better is that the Hong Kong entry form is easier than the US one. And when you enter the Schengen zone in Europe, there is no form at all! Just front up to the border control with your passport and be prepared to answer a question or two.
Make sure you keep print outs of your itinerary with you. You may need to present evidence of a booked return/onward journey at check-in.
A minor note which should not matter: make sure when you arrive in Europe, you receive a passport stamp showing your entering the Schengen zone, and then afterwards, you have a stamp showing your
exiting it (once you fly back to Australia via Hong Kong). If you do not receive either stamp, make sure you keep boarding pass stubs etc. as evidence of travel. Otherwise, the Schengen border control may detain you or on a subsequent trip if they are not convinced that you didn't overstay / attempt to overstay.
Although it will make next to no operational difference to you, Switzerland is part of the Schengen zone but it is
not a member of the EU.
