3 Days in Auckland!
I would suggest getting the ferry to Waiheke Island and having meal at one of the vinyard restaurants. Waiheke used to be hippy heaven, now it's all about the wine.
We had a meal at Mudbrick; it was beautiful food. Quite expensive but the view across the harbour towards Auckland is stunning.
Te Whau wine has a good reputation; their menu looks great.
Otherwise, Ponsonby Road has loads and loads of trendy bars, cafes and restaurants. It was really busy last time I was there a few years ago. Great for people watching. I don't know any particular places off the top of my head but cuisine.co.nz has loads of reviews.