Pilotdude, Physics is a minimum requirement, a pre-requisit if you will. Your best option if you want to do the cadetship is to enrole in a TAFE night course, get the actual complete year 12 certificate. Bridging courses are not acceptable. You may also consider the fact that they accept certain tertiary equivalents.
In terms of going the GA way or not, well, it depends on what you ultimately want. If its airline flying, multicrew stuff, consider looking into this new MPL bizzo. If you want to explore differnt facets of flying, GA is certainly an experience.
As for UNI, if its not what you really want to do, or doesn't help get you there, whats the point? Why waste more time than you have to?