I like the way you think, but NZTR have say over when/how a club races, and would be likely to refuse a raceday licence if the proposals didn't sit well with them.
It is the 'chopping up ' of existing circuits that has buggered some of the traditional days. The West Coast of the south island is on the way out with the elimination of the Hokitika track for racing purposes, and can only be followed by the others at some stage as stakeholders see the writing on the wall.
Similarly, the separation of Nelson/Westport/Blenheim has led to two of the three venues no longer used for galloping, with the third - Blenheim - hanging on by the skin of its teeth.