Welcome back. I think it'd be a real shame not to have your DSLR along with you so may I suggest something like the Topload Zoom AW
I use the Topload Zoom 2 (slightly smaller and not "All Weather") slung from my belt which gives great access to the camera without being in the way while walking. Obviously you'd also need space in your backpack for extra lenses and accessories.
A number of our members are based in NZ and so will be able to offer better advice than I can but, delighted though I am with my G10, my memories of Fiordland suggest that the G10 might struggle a bit if you plan to use it much in the dark conditions under the forest canopy.