I am flying into AKL and out SYD with 26 days in between. Would something along these lines work:

2 days in Auckland
10-14 days in the South Island (driving to multiple day hikes and other outdoor activities)
3-4 days in Cairns
3 days in Sydney

This leaves me with 3 days which I can spread around these destinations or throw in Wellington/Melbourne/etc. Should I spend more/less time in one area? Consider another city? Thanks!