Hi bt95,
The first thing I'd recommend you do is to join the CVDPA. You are quite correct, thanks to the efforts of Arthur Pape almost 25 years ago you can now have an aviation career in Australia. It wasn't always like that though and his victories at the AAT did not come easily. It was only through lots of hard work, dedication and many dollars that we are as fortunate as we are now.
As you've no doubt read through these forums, things are heating up again in Australia with another legal challenge now well underway at the AAT with the aim being to finish the job started all those years ago and to prove once and for all that CVD's do not pose a safety risk. We can then use this experience to put pressure on ICAO and the rest of the world to bring about further changes globally. All this can only be done though through people joining the CVDPA and becoming actively involved.
To answer your questions:
1. You can achieve any licence you want in Australia. I've held an actual ATPL now for 8 years, however as I've failed all colour vision tests, I may not exercise the privileges of that licence. If you fail the tests, your class 1 medical will be issued with a restriction 'not valid for ATPL operations'. However, that will not stop you from exercising full PPL/CPL privileges day or night, VFR or IFR. If you pass any of the tests, you are granted a full unrestricted medical. However, you will normally only be granted one shot at each test.
1.1. Besides the Ishihara & Farnsworth Tests, the other two options are the control tower signal gun test and the practical lantern test (conducted at the Victorian College of Optometry). The latter test is designed to simulate a PAPI, however it is nothing like the real thing at all. It is simply a modified Farnsworth Test. I fly PAPI's all the time with no issue whatsoever, yet I failed this test miserably.
2. ATPL is not necessarily related to RPT. Basically an ATPL is required to be pilot-in-command of a multi-crew aircraft. A CPL is required to be pilot-in-command of a single pilot aircraft (or co-pilot in a multi-crew aircraft).
3. There are still plenty of career opportunities as a CPL holder. eg. general aviation charter/instructing, freight in single pilot aircraft, RFDS etc. You can still also use CPL privileges to become a co-pilot in a multi-crew aircraft (including jets), you will just be prevented from becoming a Captain. This is the situation I and many others in Australia currently find ourselves in. We are flying for airlines as First Officers, each of us with many thousands of hours experience, however are discriminated against from becoming Captains.
4. Flying using PPL/CPL licence, you can exercise full privileges, even if you fail all colour vision testing. You can fly at night and IFR with no problems or restrictions whatsoever. Similarly, flying as an airline co-pilot using CPL privliges, you can undertake exactly the same duties as colour normal colleagues.
5. Definitely doing a uni degree is an option - I won't go into the pros and cons of it here as it is not relevant and there are plently of other posts on these forums which examine this issue. Almost all charter jobs and definitely airline jobs require night & IFR ratings etc, but remember you can still do all that even if you fail colour vision testing.
6. I'm not sure about the requirements these days, with ARN's. I'd imagine you probably need one though before you can go for your medical. I wouldn't be too concerned anyway, as you can still exercise full CPL privileges regardless of how you perform on the colour vision tests. If you pass the tests, you just get the extra bonus of being granted ATPL privileges so that you can one day become a Captain.... but that will still be a long way off and hopefully through people supporting CVDPA we can change all that in the future anyway.
Hopefully that answers all your questions! Feel free to send me a PM if you would like.
Good luck with Year 12 and don't listen to anyone who tells you that being a CVD means you can't fly. As you'll soon learn, it doesn't make any difference at all - our challenge is to get that message out there and to hold these beaurocrats around the world and their irrational decision making to account.