For nz
Savea
Moody
Whitelock
Savea because he is our point of difference, the world class player who can win a game we are otherwise not going to win. By contrast if cane gets injured you can put Todd there and haven't lost much (though I am a huge cane fan, Todd offers similar attributes). If you lose read you can play savea at 8, who would do a bette job, and use luke or barret at 6; you would definitely lose a bit in total but the replacements are pretty good.
Moody is the obvious one. I'm quite shocked
@Larksea and @bobby_m didn't pick this one. Moli and ofa as a loosehead are a long way behind moody; but also because we don't have franks we kinda need the experience of moody for when the opposition uses all their experience against us. While laulala is an excellent scrummager, in terms of pure talent, he doesn't have the experience against different techniques and tactics like franks does.
And whitelock. At this stage Brodie is already injured until the quarterfinal at least, and then won't have match fitness, and already hasn't been in top form as late. Whitelock s ruck clearances and Linout work as well as leadership will be vital, particularly in the mix we have chosen with a relatively small 6 who isn't the best line out forward.
When Ireland beat the all blacks Ardie savea was the best on the park, followed by furlong and healy then the rest of the Irish team. But furlong and Healy in particular made the difference, as they were just so much better than their New Zealand propping counterparts. So much so that franks hasn't made it to the World Cup.