3) There will be too much backlash from a deal with Labour and the Greens
If NZ First choose Labour and the Greens, there will be a massive backlash against the party, according to National Party blogger David Farrar: "For the first time the biggest party isn't Government. Sure the political scientists and Twitterati will proclaim that is how MMP works. But they are not representative of the population... Those who say there will be no backlash don't understand that not everyone is a political scientist. Many will see the Government as illegitimate. It will be called the coalition of the losers" - see: Why my heart wants Winston to choose Labour. In addition Farrar suggests, "Winston choosing Labour and the Greens (regardless of whether or not Greens get Ministers) will go down like cold sick in much of rural and provincial New Zealand."
4) If NZ First wants to sit on "the crossbenches" outside of government, then National is more likely
According to Mike Hosking, if NZ First chooses to stay out of government entirely, it will likely choose National: "If a confidence and supply deal is the way we go ...you'd have to favour National, if for no other reason that they as a singular party have more support that both Labour and the Greens combined. For a third player to support two other players into government that can't together equal the support of the single largest player is not democracy ... and wouldn't go down well at all" - see: Major parties acting like subservient wimps.
National's superior vote is just too strong for NZ First to ignore
The "moral authority" of National to govern means the incumbents are likely to be chosen by NZ First, according to John Roughan, writing on the day the final results came out: "When the final result of the election is declared today National is almost certain to have its victory confirmed. The margin over Labour will probably be reduced but still decisive. We should pause to acknowledge what an historic result this is" - see: A fourth election victory is truly historic. Similarly, see Roughan's earlier column, A personality cult decides our next government.
6) National might be more able to help NZ First with a legacy
National Party sources have told Richard Harman that the party can't necessarily compete with Labour in offering policy concessions to NZ First, but there might be other gains they can offer, such as helping Ron Mark or Shane Jones win their electorate seats at the next election, in order to secure the survival of the party when Winston Peters retires - see: Winston faces a dilemma - policy or legacy.
7) Many commentators deem National the likely winner
The Spinoff website asked a number of pundits the question: Which way will Winston leap?. Most of those surveyed seem to think National will emerge victorious. For example, Steve Braunias explains why: "I think Peters won't want to be part of a loser triumvirate. He's great at picking winners. He'll go with National. Also he'll be the equal or the better of English, alongside him in government; alongside Ardern, he'll just look like a silly old second-rate prat."
8) Following its traditionalist inclinations, NZ First will opt for National
Stuff political editor Tracy Watkins says National has the edge to become government: "the odds are still weighted in National's favour. Peters is an old-fashioned politician and, despite the theatre, will be taking seriously the weight of public support behind National" - see: Winston Peters is in the box seat, and don't we know it. Watkins sees a re-run of 1996: "Peters' reasons for going with National back then were the same ones that will take priority in 2017 - whichever of Labour or National he chooses, it will be based on Peters' belief in it being the most stable and more durable of the two options."
9) NZ First is conservative
According to veteran political columnist John Armstrong, writing soon after the election, Winston Peters will be very aware of "the risk he would be taking in hitching his unique brand of conservatism to the political correctness exhibited by Labour. Peters likes to talk a lot about bottom lines. But his ultimate bottom line is the survival of New Zealand First after he (eventually) retires from politics. And that will incline him to lean more in National's direction as post-election negotiations progress over coming weeks" - see: Winston Peters' ultimate bottom line.
10) NZ First has lost its more leftwing supporters
Much is being made of NZ First supporters being more favourable towards a coalition with Labour. Yet during the campaign, many of these supporters shifted to Labour. Colin James explains: "If you had to assign New Zealand First conference delegates to National or Labour, most would go Labour. The same majority applies to its policies. But the fact that New Zealand First's support halved after Ardern was made leader might mean its residual supporters are mostly National-leaning" - see: English on top but facing a stronger Labour.
Finally, for the latest in coalition satire, see Toby Manhire's Hi Winston, just a few thoughts..., Ben Uffindell's Winston Peters said nothing in talks with National, just walked around room with a box cutter, Scott Yorke's These coalition talks and Steve Braunias' Secret Dairy of the coalition talks.