I was thinking of doing that same thing.
Spending a week with a group doing all the touristy things on the bike, but then spending a week either on the north island or in Australia.

The groups I've looked at also do other things besides biking. But I've tried to look for the ones that are doing things that I might be interested in (like kayaking). I'm still looking at all the options. Thanks for heads-up on VBT. I'm only 28 so a senior trip is probably not my cup of tea.

I'll keep you posted on what I find out.