The entry into the House of Representatives of "Unelected List MPs" is a common complaint about MMP.
And while the response: they were elected by the party vote, and voters were told who was on the party lists before they decided their party votes is a pretty good one, it's not enough for a lot of people, so mechanisms by which voters can have a greater influence over the exact membership of the House are often proposed.
A frequent suggestion is that, instead of having a list, party vote seats (I guess, you can't call them list seats!) in the House would be filled by the best runners-up from electorate races: by the candidates for that party who scored the greatest percentage of votes in electorate races, but without winning those electorates. It is argued that these people have established some evidence that they have personal support to be in Parliament (or at least more personal support than those who were candidates for their party who didn't do as well). There is something in this argument, although I'm not a convert to it. At least yet.
Given the (hopefully) upcoming review of MMP, and the likelihood of this being proposed in submissions, I thought I'd take a look at this through a counter-factual, using, as an example, the newly elected Green caucus. Except it's quite different. If, instead of a list, empty parliamentary places were filled by best losers, the Green Caucus would have been:
Dora Roimata Langsbury
Jack Taotokai McDonald
Eugenie Meryl Sage
and the possibility of Aaryn Barlow
And gone would be:
Julie Anne Genter
and the possibility of Mojo Mathers
If I get some time, I may look at the other parties (they're slightly harder to do, because the other parties included list-only candidates), but I suspect there would have been a number of unexpected MPs, perhaps including some welcome returns. As you can see from the Green Party above, there might be a very different parliament: one that might have included our fastest ascension from the Youth Parliament!
Of course, this somewhat random group shows one of the major problems with using a best runners-up system (and with open list systems): the number of MPs a party gets was determined by its party vote, but without a closed list, no-one can know who those MPs will be. Given that I'm inclined toward some form of open list, this is something I'm going to have to think about (although at least an open list has the advantage that the overall list is determined by the voters across the country, rather than in particular electorates, where perhaps the reason someone did well, was that they were one of only three or four nominees).