Yeah, Elliot stay IMO as well.
I would push McCullum down the order to six/seven, push Guptill up to open.
Then you can bring Williamson into the side at number three, where he's been scoring all these runs.
So like this:
Ryder (6/7/8)
Guptill
Williamson (6/7/8)
Taylor
Elliot (6/7/8)
McCullum (wk)
Oram/Franklin (4/5) (only one can play, in the this team I have named)
Vettori (c) (4/5)
Mills (2) (when fit, otherwise Southee)
Bond (1)
Tuffey (3)