Concerning ID, a lot of spiders/spider groups aren't well known (though you probably know this already) so ID down to species, sometimes down to genus, is often difficult to say.
Dolomedes sp: Please refer to page 215 of White & Anderson's guide. I believe this resembles the bottom image taken from Hill Top NSW which says: "This is a very cool spider, but the nickname is actually in reference to the location which is a fairly cool region. Many species have blazes of colour (often white) along the edges of the carapace" I think the general shape, abdomen pattern, leg pattern and general carapace pattern matches. Plus, the text says there can be colour on the edges of the carapace, and there would probably be individual variation. As for the location, Hill Top is in around about climate zone 6, while we're in 7 so if they are distributed according to cool regions, this fits too. Even just based on the body shape, I think Dolomedes sp fits best.