I would try to block out 2-3 nights at the end of your trip in Wellington. It would probably be nice to unwind after all that driving by staying in the 'big city'. Given your schedule, I would maybe spend some time up in Marlborough/wine country for an additional day or two before making the hop over to Wellington (or add something in the glaciers, like helicoptering to the glacier and going ice climbing).
For your day 12 drive - Wanaka to Fox is going to be LONG. I don't think you are going to feel like hiking by the end of it. I would recommend finding a nice hike in Mt. Aspiring National Park, which you will be driving through, and doing that instead. YMMV, of course, but I drove the other direction...it's a long one, even though the scenery is gorgeous. I would also recommend picking one spot (IMO, Franz Josef, which has marginally more going on) and basing yourself there for your glacier stay. Doesn't make sense to haul your stuff very close by for that one day.
3 days in Queenstown would start feeling long for me, largely because it was overridden with tourists (yes, I know it's ironic saying that, since I was one of said tourists). I would cut one night and add another night in Te Anau (hopefully staying @ Fjordland Lodge
) and maybe do something like the heli-hike the lodge offers to the Kepler Track, which affords you gorgeous views (and you can get some decent hiking in as well). And don't forget to visit Rippon...I may have mentioned in one of your previous threads, but if you swing through Wanaka, the views there are absolutely fantastic. Of all the wineries I have been to, that is the one that sticks with me the most vividly.