They weren't more consistent though. They ended up on exactly same amount of points and benefited from a point in a washout, just like Pak did.
It was out of our hands as soon as Wahab was out vs the Windies. It was a death knell to our NRR. The two games we lost subsequently were to two teams that no team would be ashamed of losing to.
Likewise, my point isn't necessarily to say that NZ are a horrible team or that Pak were even unlucky. I just think to say that NZ were a more consistent team is a bit of a misnomer, and the NRR system needs looking into. It's not like GD in football, where the games are a level playing field.
Cricket is so open to the elements, and even the concept of chance. The difference between a win and a loss in this world cup was increasingly hinging on the flick of a coin, for example. Batting first would always allow you to rack up as high a run-rate as you want or can. While batting second, even if you win handily with multiple overs to spare, won't be fully reflected in the margin of victory. Say, you chase down 200 in 25 or so overs, you still would likely be going slower than your potential because even with a low total, there will be scoreboard pressure, the opposing team will set defensive fields, as opposed to attacking ones when bowling first, etc. NRR takes none of that in to account.
That's why the chases v Afghanistan and NZ, while we took them deep; it wouldn't have made much of a difference to our NRR if we got them with overs to spare, because the low totals would have capped our RR in any case. If we batted first, especially v Afghanistan, I have no doubt we'd have posted a much more resounding total and would have ran through their weak batting line up with consummate ease. That would have likely reflected in a wide margin of victory and a much larger NRR impact. Likewise, NZ, though the swing would have been more pronounced if Babar hadn't slowed down in the lead up to his century, but even so, it was only a case of 3 or so overs so not sure how much difference it would have made.