But ultimately the tax is much more likely to be judged on who it will affect among individuals and businesses.
The fact that the starting point in terms of calculating gains is not retrospective will help its saleability enormously.
That is especially so in Auckland, where homeowners are sitting on huge capital gains recently in house value and are now facing a flattening housing market.
Had the report back been in the midst of the house price inflation, the sell would be more difficult.
If a tax law is passed to take effect from April 1 2021, any gain will be calculated with April as the start date.
The rules around farms promise to be the biggest battleground in the next couple of months, with New Zealand First leader Winston Peters tempting to minimise the effect on them.
Businesses will be disappointed that there is no support for progressive taxation for businesses in which smaller businesses have lower tax rates.
And it is difficult to see how a proposed capital gains tax will go any way to increasing investment in New Zealand's famously shallow capital markets.
Little has changed between the Working Group's interim report in September and the final version.
And even for a final report it is not especially dogmatic in its presentation.
It invites the Government to think about applying a capital gains tax to some assets only and says it could think about phasing or grandparenting some or all asset classes.
Cullen has gone out of his way to enhance its beauty and its chances of being sold politically, although as a former Finance Minister he knows to expect an onslaught of criticism from some quarter.
As Cullen put in: "People are very good at beating their chest but not using their brains."