The main reason that the 1970s fashion for so-called native gardens ended in disillusion was the lack of pruning, resulting in shrubs getting not only too big but also badly out of shape. This happened because people had imagined Australian species would take care of themselves. It is a prime example of treating Australian plants differently - by contrast, nobody has ever assumed exotic shrubs could be so totally ignored.
The best way to create a neat, dense, compact shrub is to trim it early in its life. This may mean sacrificing the first year's flowers, but the reward will be a nicely shaped shrub covered in flowers the year after. Continue to prune annually after flowering. If you have mature Australian shrubs that have become straggly after some neglect, reshaping may be possible if the stems you want to prune still have foliage. But if the shrub has become too woody, so that the place where you want to prune each stem is devoid of leaves, it is unlikely to produce new shoots at those points.
Instead, as a last resort, try lopping it off at the base. Again, this harsh treatment parallels natural events - such as bushfire or grazing by animals - and many Australian plants automatically respond by shooting afresh from the base. By pruning lightly and regularly you can prolong the flowering period of certain plants, banksias being good examples. Nip out each flower once it is spent, as this produces a more compact habit and new flowers. It is exactly the same routine that you probably already practice on your roses.