You’ll have more choice of keycaps and boards if you use the US layout but it depends if you need to use accented characters and the like which I would guess would be more likely to be available on ISO sets..

I used UK ISO for years, and I'm not from the UK but it was just what I could get my hands on. I switched to ANSI when I got into customs for the keycap compatibility. I miss the big ISO enter but I like the look of the ANSI one more, and the tiny left shift was awful.

Yes. The chunky enter takes up a lot of space for small form factors though.

Unless ISO layouts are all that you've used so far, go ANSI. US international has key combinations for a lot of Special Characters.

How you program your keyboard then should mostly depend on what layout your pc (or others that you may want to plug your keyboard in) is typically set to.

For example: I'm German and I need a way to type umlauts. I could set my pc to ANSI International and use qmk trickery to put the shortcuts for an umlaut on any single key, but then my keymap would be scrambled if I used the keyboard on any other device.

I’m Norwegian so I’m used to ISO with æøå instead of ‘<> or whatever. I am very open to new layout though and I’m even considering trying son Dvorak or Dvorak-like layouts. The season I’m asking this question is because I only use English on my “toy computers” like my Raspberry Pi’s, Arduino etc. so I’ll use some kind of English layout for those computers.

I dislike ISO layout with intensity

May I ask why?

It's not that there are more Americans, it's because more actual countries use the ANSI layout.

I'm in the UK, but dropped ISO years ago in favour of ANSI. I don't need to worry about whether a keycap set supports ISO... or a keyboard for that matter. I also don't have to put up with the ridiculously tiny left shift key either. I also think ISO looks crap and unsymmetrical, but that last one is just personal preference.

US using Uk and I hate it. So much. If I could get windows to cooperate and put the 'keys' back where I want them (the @ sign goes under the 2 damn it!) it would make me very happy. My keys are US layout.

I’m Mexican, we have two “common” spanish layouts “latin american” which is ANSI based and “spanish” which is ISO based; the alt symbols are anoyingly distributed in ISO, I think big enter keys are dumb and is not even necesary to have a localized keyboard, I find it way more comfortable to write in an international US layout to get “eñes” and tildes. ISO is a stupid that just exists cause european countries insist in not using any standard that comes from the US which makes sense sometimes but is just stupid for keyboards

The best would be to just use ortholinear