Keep it simple, build infrastructure
Like typical bean counters, you're obsessing over minutiae and getting carried away with theory. There is no such thing as 'fair". How to give everyone a chance however is to educate and provide employment. Do that by building infrastructure, it has been sorely neglected these last three decades, and obtain full employment that way. Employment = saving = home ownership = food on the table = children well schooled = build more infrastructure. And unleash NZ's mining potential, there are limitless resources being ignored (NZ is essentially made of coal and limestone). Then tax very little, scale government small, only essential services, defence (2% of GDP), health scale away from large hospitals and into day clinics in the suburbs, educate by getting the teachers to stay in the classroom (incentives currently are to get out of the classroom) and make lessons practical, the rest only the essentials, end the Nanny state.
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