Timing is difficult for me but it would be great to have/attend a local WA meet up
My favourite spot is just east of Mundaring Weir, not bad skies for being reasonably close to the city. Being a water catchment area gates and obstacles cover some of the prominent gravel roads accessing the area so provides some deterrent to unsavoury types. Further east you go the countryside becomes more open woodland with plenty of spots
Not familiar with wheatbelt destinations but kokerbin rock seems to be popular. Further afield I was going to inquire here
http://www.stirlingrange.com.au/home.html