I'm from New Zealand and have been spending my late 20s going around the UK and Canada on 2 year working holiday visas. My work experience is in marketing in senior IC/mid level management roles.
The impression I get from most countries visa options is that they're happy for people like me to come in for a few years, work, pay tax, and leave. I'm surprised that even on a temporary basis this kind of activity seems impossible in the US (unless you are quite specifically a student). I'm also aware that the US system is very complex, so are you aware of any visas that I should be looking at in the US which I just might not be able to find?
You are right, it's harder in the U.S. and there's no open/general work authorization visa. But there are ways to do your own thing in the U.S. through the J-1, E-2, or O-1 visa.
It's a longshot, but don't forget to apply for the DV lottery. Due to the unusual structure of the program NZ citizens have a higher chance of winning. Short of marriage it's by far the best visa, since it's a green card (permanent residence), not a work visa.
The is (or was) a visa for NZ recent graduates to work a couple of years in the US.
There's also a US route if you can get Aussie citizenship somehow too which Australia has recently made a lot easier for NZers.
The impression I get from most countries visa options is that they're happy for people like me to come in for a few years, work, pay tax, and leave. I'm surprised that even on a temporary basis this kind of activity seems impossible in the US (unless you are quite specifically a student). I'm also aware that the US system is very complex, so are you aware of any visas that I should be looking at in the US which I just might not be able to find?