A Coronet may be more accessible to NZ groups and provide greater opportunity for additional pageantry, local awards and recognition, but there are fears that a Principality would mean less interaction from Crown (and Australians in general), fewer local Crown events and reduced Kiwi entries into Crown Tournaments.
There will be costs involved in establishing and supporting a Principality. The SCA in New Zealand has the financial resources and management experience to afford this.
Approximate levels of group funds as reported by SCANZ (31 March 2020), show:
Such a decision would ultimately rest with the Kingdom Seneschal based on the results of a formal membership poll - but one group being able to opt out when the rest are keen to go ahead is not likely to be an option.
The main factors requiring an all-or-none move relate to the need for contiguous geography, viable numbers, regional coherency and national jurisdiction.
Based on the CF and surrounding discussions, we seem to have the following responses:
Official Information
https://www.sca.org/wp-content/uploads/2019/12/govdocs.pdf
See especially p16 and p23