Actually I just discovered in my Samsung TV app list an app called "Freeview" which I don't think has always been there (maybe I just overlooked it) that presents a combined view of all on demand content from TVNZ, Three and Maori - or you can select content from each individually. This allows streaming without the need for an aerial connected.
and no way to bypass all the adverts.
I mostly record all my TV and watch later so I can FF thru the adverts. Streaming TV does not allow this.