OP - How big a deal is it to you if you misconnect and arrive a day late? If your arrival in SYD is time-sensitive, don't do this as the risks of a misconnect are, of course greater the shorter the connection time with no reroute.
Will DL grant you a more favorable reroute on the domestic hops? Not likely unless it is clear that there are enroute issues and even then. You purchased the indirect routing for a reason presumably.