Q400's... much as I hate them, they are the way forward for a next-gen domestic carrier. More to the point, an innovative approach to service and a bit more "fun" would be nice... Air NZ's domestic service is pretty tired.
Beech 1900's are too small and yesterday's technology.
Air NZ needs to work out how to grow the domestic market so that the Q400 is a one-size-fits-all solution. Running three types is just stupid.
In other words, go have a chat to Easyjet or Ryanair...