Dunedin/Invercargill v. Abel Tasman/Nelson/Blenheim or Neither???

The places you mention are certainly great scenic locations, but the order of visiting each of them in a limited time is important. The order you've given so far is disastrous!

Mt Cook and Milford Sound are at the end of their respective roads, so thay have to be fitted in so you don't back-track further than necessary.

In principle, the South Island in not necessarily a "join the dots" country, it's more a continuum of scenery, where a fixed itinerary can limit your options.
There is also the inevitability of rain.

Try searching the records of this branch. The 2 week tour of the South Island is a perennial topic.

It's useful to know an enquirer's approximate level of physical fitness, and special interests or non-interests.

Thanks for the reply. Our plan is nowhere near finalized and is still a work in progress. In the mean time, which region would be a beneficial add-on to our trip based on the proposed cities listed above?

It does seem a slightly funny order.

Last year we did Christchurch, Kaikoura, Blenheim/Picton (for a wine tour), Nelson, Abel Tasman, Westport (for a caving trip, Fox/Franz Josef (we did the walk at Fox and stayed at Franz Josef, Wanaka, then Queenstown - followed by a long drive back to Christchurch.

We did all this in 10 nights quite happily.

Thanks Mitchlou84!

The places you named can be generally seen in 10-12 days so you could fit in EITHER Dn or ATNP.
Dunedin offers great opportunities for a wildlife tour (Elm is recommended for penguins, sealions & fur seals), or for museums, restaurants, Speights Brewery etc; whereas ATNP is more for activities such as kayaking & hiking.

Thanks for the input so far! So, here's my itinerary for two weeks in late February. We're trying to pick a mix of great sights, mild outdoors and relaxation. I realize this might be a great deal of driving, but two weeks is all we have and need to make the best of it. We'll be sharing the driving time between two of us. Unfortunately, we have to come in and out of Christchurch due to flight pricing.

Day 1 land in Christchurch at midnight, stay in Christchurch hotel
Day 2 drive 3 hours to Kaikoura, whale watching tour and drive 2 hours to Hanmer Springs, stay in Hanmer Springs
Day 3 do spring hot pools and visit Hanmer Springs, stay in Hanmer Springs
Day 4 drive 3 hours to Punakaiki, visit pancake rocks and drive 4 hours to Fox area, stay in Fox area
Day 5 see glacier via chalet lookout, visit glacier and see Mt cook from there, stay in Fox area
Day 6 drive 5 hours to QT (visit haast pools on the way), stay in QT
Day 7 QT wine tasting, gondola up queenstown hill, relax, stay in QT
Day 8 drive 2 hours to te anau, glow worm caves, stay in te anau
Day 9 drive 2 hours to milford sound (boat tour of milford) and return drive 2 hours to stay in te anau
Day 10 drive 3 hours to Wanaka, stay in Wanaka
Day 11 stay and visit in Wanaka (wineries)
Day 12 drive 3 hours to Lake Tekapo, visit church of good shepherd, stay in Lake Tekapo (or Pukaki)
Day 13 drive 3 hours to Oamaru visit Moeraki rocks and drive 4 hours to Akaroa, stay in Akaroa
Day 14 visit akaroa penguin habitat, stay in Akaroa
Day 15 drive 1 hour to Christchurch and depart at 6:20am

Any thoughts on the itinerary? Does the order of sights work? Some adtl questions we have -
Better to visit and stay in Akaroa or Christchurch?
Are the Moreaki rocks worth the extra couple hours it takes us out of the way?

Thanks in advance for any advice.