MikeB4:
I agree I had forgotten about Nikki Kaye she would be a very good choice. I am probably wrong but I kind of recall that she has said that she does not want the leadership role because of health concerns.
The latter may well be true as well. But she's just going to be the victim of the usual schemers and hard right types eventually - National seems uninterested in anybody for the front bench other than your Bridges, Collins and Bennett types. All of whom are utterly repellent to social progressives/political centrists like me.