Auckland will be easiest for visiting wineries. Plenty of tours on option at both Queenstown and Auckland, but most of the Queenstown ones IIRC are single winery.

Flight to Milford Sound is amazing (even better than the spectacular flight into Queenstown). Its all very small a/c by local operators (so no miles). You get to fly through the southern alps with close views of Sutherland Falls (one of the highest anywhere) as well as Milford Sound of course. The valleys are so narrow that flight path differs going in and out. Downside is the Fiordland area gets a lot of rain ("only" 6 metres annually at sheltered sea level and perhaps 10 metres in the mountains) so to be sure of good views (or even a/c operating at all) plan on being at Queenstown at least 3 days to maximise chances. The cruise is nice - see more mountains and waterfalls up close, dolphins, see the amazing entrance to the sound from the seaward side, etc. If the weather is wet then take the bus which is a long day return trip. You can also choose fly one-way and bus the other.