It can be said that an actuary should deal exclusively with numbers, but I am also an expert in insurance plan design and implementation. In the case of an insurance program, you must provide eligibility and access to benefit criteria such that the system will be able to function efficiently.
In this system, requiring people to contribute for life after having drawn a few benefits is to my mind pointless, particularly in the case of sick benefits. As for parental benefits, they become a form of loan that the government grants these people, but then these beneficiaries must pay the money back for the rest of their lives. Furthermore, given that self-employed workers can usually expect to see their income increase as their career progresses and their expertise improves, they will eventually be contributing an amount based on higher earnings than those that the benefits were calculated for.