After sleeping on it, it suddenly dawned on me that I should have just booked us on NZ5 anyway, which leaves at 10pm, rather than NZ1 at 9.15pm. I still make the same connection to BHE anyway (it's really interesting - to me anyway! - to see how the flight schedule to BHE is cut back during the holiday period, btw. I've never seen so few daily BHE-WLG flights as during that first couple of weeks of January.)

This means we now have a 3.5hr connection through LAX, which I think is about optimum for separate tickets - long enough to be hopefully not too stressful, but not so long as to be nightmarishly interminable.