I'm certainly no expert in economics, so the following is probably guff, but here goes:
As an employer, I shudder at the thought of having to pay 15% super for employees. In order for our business to remain at current levels of profitability or better, either total wages would have to remain the same - meaning a lower take-home pay for employees, or total payroll would have to remain the same - meaning less employees. Small businesses in Australia are doing it tough atm, and any increase in compulsory super paid by employers would need to come out of existing gross wages I feel, which would no doubt lead to a lot of very unhappy employees. It is difficult enough for young people to save for the first home deposit/ pay the rent/ allow one parent time off for having babies etc - without them having to endure an effective paycut in order to have more of their wage put into super. Personally, I think it more important for the home loan to be paid down as quickly as possible whilst young, then plow money into super once the non-deductible debt is under control.
I can certainly see that an aging population is a problem, and it would be very irresponsible to assume that pensions will remain available in the future on the same basis as at present. Tax revenue to pay for infrastructure needs to increase - not be siphoned off into more and more pensions. However, I would prefer that the onus to look after your own retirement becomes more your own responsibility, in that if you've provided well enough for yourself you retire when you wish, but if not, you may need to continue working longer than at present. Raising the pensionable retirement age makes sense to me, as we are generally healthier at 65 than prior generations, and are living longer. It once was that the average man would retire at 60 and die at 70 - happily this is no longer the norm. Lowering tax rates for those over say 55/60 would encourage people to stay in the workforce a few years longer and allow for that extra net income to be put into super. Leaving the compulsory super contribution at 9% should allow most people a comfortable retirement if they plan and manage reasonably well, whilst also allowing younger people greater choice as to where they wish to direct their funds- if I were 25 again I'd be quite concerned about the legislative risks of super and would prefer to keep a good portion of investments away from governmental interference. If I'd worked and saved all my life only to be told "sorry, but we don't trust you with a lump sum, so here's what you can spend per month of your own money, try not to die before you get to enjoy some of it", I'd be very, very ###### off!
Sorry for the ramble, just my