Most RAAF candidates would have little if any flying experience as it's not an organisation on the career radar once someone has their CPL in hand. Tests normally include eye/hand coordination, reaction times, ability to rapidly assess information, response to stress, intelligence, teamwork etc.
Already having a licence won't help if you don't meet their criteria in the other areas. MIlitary pilot selection is tough with a high chop rate for those not meeting standards during training.