[Aust-NZ] Best approach to adding vector layer to NZTopo TMS

[Peter]

I am working with Gavin from topomap.co.nz (a topomap viewer targeted at outdoor users) to migrate the site to openlayers using NZTM, baselayer tiles from the topo50 etc geotiffs.

Thus far the thinking is that the baselayer is a TMS layer, because it changes about once per blue moon, and is fast to deliver and render. However we are working on adding a political layer, which comprises among other things TLA and region boundarys, doc estate, doc facilitys and similar that either doesnt appear in the baselayer or is more dynamic in nature. User maintained hut listings and public right of way entrance points are likely.

My question is what is the best approach to serve this layer? My as yet limited knowledge sees these choices:

a. make a second TMS layer, redone manually from time to time
b. same as above but using tools like mapnik.
c. create a mapserver WMS with tile caching to make updates easier.
d. simplify the polygons and deliver as a ajax strategiedvector layer to openlayers.

Wed appreciate any advice about the pros and cons of these methods?

Theres a qgis screenshot of the draft layer here:
http://www.zoneblue.org/files/political-concept.png

And an openlayers proof of concept here:
http://www.zoneblue.org/map/openlayers.html

Regards

Peter Scott