Goodhue will be the long term centre, Ioane can therefore keep being the worlds best winger for a few more years.
There is no outstanding centre in NZ ... currently. Goodhue has nowyet to play a test match at this level. I think Ioane has the necessary dimension to become what the AB are looking for. The left wing spot won't be a problem since there are incredibly promising young guns coming (Caleb Clarke, Leicester Faingaanuku). So it is urgent to test Ioane there as the French team is not a great threat and the RWC is coming next year.
The Charlie Ngatai of 2018