This all comes back to the ridiculous contracting system in Australia IMO..
As far as I am concerned the whole top up system is just a farce. Do away with top ups altogether.
Incentivise selection in a graduated system which progressively pays more the further you go. The ARU can budget quickly and easily and wont end up having massive contract payments to players who are injured and not available, sometimes for extended periods.
Reward actual performance and encourage true competition, instead of rewarding form from 18 months or longer previous to the actual payment.
This gets away from the marketable individuals getting paid huge amounts whilst those players also part of a team don't get nearly the same. Rugby is not an individual sport and individuals rarely win games. The individual if they are that marketable could be free to promote products and services away from the team in any way they want, and thereby capitalise on their individual profile, in addition to what their team produces.