Other superannuation benefits are voluntary. It depends on what the company wants to offer.
You can design any scheme You want, but remember that it needs to be fair and attractive enough to workers to be an incentive. If the period is too long, workers will simply ignore the scheme and it will not achieve your intent to retain talent
For example if you say superannuation will be after 20 years, which employee will bother ? Do any of them think they will work for 20 years for you ?
16th June 2016 From India, Mumbai
19th June 2016 From India, Madras