A simple summary from someone who does exactly the same up to a dozen times a year (although not from ADL):
1) You can have your baggage checked through but absolutely make sure you have your flight details there (flight number, PNR and ticket number preferably)
2) Allow a lot of extra time as some agents struggle and can take a while
3) Make sure that the names on both tickets match, including any middle initials used on the ticket, as it can cause a bit of a hiccup trying to through-check baggage from QF if they do not (although not un-solvable, it can cause a bit of a delay and if the agent isn't helpful, it can actually end in a 'no')
4) You can definitely use the airside QF bus.
5) Standard QF domestic allowance is 32 kg x 2 in J. Paying online in advance for excess baggage will save you $10 ($40 at the airport, $30 in advance online). Make sure that you have the excess baggage receipt if you pre-pay online.