Both New Guineas and Aussies show a wide range of coloration--yellows, reds, blacks, etc etc. NGs tend to be smaller and much more common than the Aussies. "Silver" Aussies (also can have many other colors) tend to be larger than NGs with big white cheek patches. There is a lot of confusion since NGs and aussies can show very similar characteristics. If you do not know what you have, you probably have a NG. I have not seen any aussies on the market so far this year and you typically pay more for them. It is also confusing as I have seen dealers sell import NGs as "australian frilled dragons". NT (northern territory) red aussies were brought in to the states and bred here selectively. These tend to be the highest priced animals and often the largest. I have not seen any this year either.
KWE has some very orange and red colored NGs that some people are calling red NGs. As far as I know, there is no established "phase" or "morph"--it is more about calling it the color that you see. Again, NGs can come in a lot of colors--I have one that shows a lot of orange, one that has a brick red frill, etc etc. The ones that some people got from James Tuttle last year come from parents that show a lot of orange.
Hope that helps.
And in my opinion, frillies are far from boring and very hardy. The only reason for them not to be hardy is that so many imports come in in poor shape. If you buy captive bred, or a healthy, treated import, you should have no problem.
Dana