Super Rugby is completely cooked. It's unworkable, not least because the three major nations are on completely different levels. South Africa are a basket case (no offence intended) economically and politically. Rugby is always going to be intertwined with politics over there, and politics and sport do not mix.
Australians just don't like rugby. It's that simple. You have the tragics (me, sadly) and the private school boys (most of whom only watch it around other sports) and that's it. We cared for about 5-10 years when we had some half decent players, and hosted the world cup. But we ****** away any money and interest in the sport by splurging on a few big stars (still doing it with Folau, Hooper etc.) and completely neglected to grow the base when we had the chance. I was in Auckland the other week and people kept telling me the Wallabies will come good again. They won't. Their performances are finally starting to reflect the relative interest in the sport here. Well below 5th in terms of viewership and around 30th for participation.
And NZ are too good, because they live and breathe rugby. No one else does, except maybe South Africa, but even then not to the same extent. They will continue to be the best rugby nation in the world, probably forever. In the long term only England will be able to match them in terms of interest and participation, and probably outmatch them financially.
How do you combine these three into a workable quasi-domestic competition across x time zones with a team from the northern hemisphere and a team from South America thrown in? It's amazing it's lasted this long.
Combine all this with the growing realization that getting your head smacked a hundred times a year actually does some serious long term damage to your noodle and this thing is more sunk than still sinking. Young kids are playing AFL and Soccer and they don't even know what Rugby is. I hear even in NZ the level of participation in Soccer is growing at a far greater rate than Rugby. The damage it does to your body really does make it a mugs game.
P.S: i'd add that having to watch the Wallabies get absolutely thrashed three times a year against the All Blacks, including the first game of the RC, does some pretty serious harm to interest as well. Particularly when it's billed as the biggest game of the year (and interest in Super Rugby is intertwined with a successful Wallabies.