The more I read the more I learn from your replies. You clear up the misconception regarding the booster. On an unrelated subject, you've mentioned that you live permanently in China- were you required to be a citizen of that country? Or do you possess a dual visa- Australia and China?Just for clarity, boosters don't increase stopping power, that is a function of braking area and friction etc, all a booster does is change the pedal weight. And of course pedal weight itself is also function of master and slave cylinder sizing, and pedal pivot ratio.
The donor car pedal pressure wasn't noticeably heavy or light either way, and since it's components are being used, and that the vehicle's weight won't be dramatically different to the donor, I don't foresee any issue really, other than possibly needing a bias valve to prevent rear wheel lockup.