NSW CDC rules on floor-space size vs outbuilding size

Sorry if anyone's seen this over in the Building New section; I've decided it's probably a bit OT over there.

Can someone please confirm if I'm understanding the NSW Complying Development rules correctly?

We have a block that's just under 600sqm.
The floorspace/coverage rules which are relevant are that our house (including garage, fenced balconies etc) can be up to 330sqm; outbuildings can total to 45sqm; and the hard surface when viewed from above can't go over some proportion which I think is 50% (not sure on that but can get the details easily - for the purposes if the following calculation assume it's 50%).

Would I therefore be correct in saying that, as long as the hard-coverage in-total doesn't exceed about 294sqm, it would be acceptable to have a house (including inbuilt double garage) with total upstairs+downstairs floorspace of about 325sqm, and a separate single-garage-plus-workshop which encloses about 40sqm?

That sounds correct.
If that is an issue in the design why don't you do the DA through your council or are their floor space ratios and/or hard surface areas worse ?

Stewie