The Portuguese layout sucks horribly for programming, especially on the Mac (brackets in horrible places), and the U.K. layout (where I’m based) sucks horribly for writing Portuguese in. The US international just works for all my purposes (including writing tiny amounts of other languages besides Portuguese and English)
Just checking you're aware that dead keys for all Portuguese diacritics are available in the UK PC layout - alt+e (´), alt+n (˜), alt+\ (`), alt+c (ç), alt+i (ˆ)
Because I never went back to the Portuguese layout after finding those key combinations.
That looks like an "AZERTY International", with no advantage over the Portuguese layout for programming, and no advantage over "US International" for typing languages other than French. It does look like an improvement over traditional AZERTY!
My choice is "US International with AltGr deadkeys". The deadkey behaviour in simple "US International" is very annoying for programming: you have to double-tap every key that could be an accent, such as single quotes or backquotes.
Yes I clicked but didn't notice the Greek overlay. It's neat. I imagine that it can be useful for math, if you're not using something like LaTeX or Emacs already. I even have something similar in my custom layout, although it seldom gets any use. That does not make it any better for programming, nor for typing in Portuguese (or even Greek).
Look, I think it's great that this thing exists and grateful that you mentioned it. I may even suggest it to some of the French-speaking juniors I work with.
It does not, however, address the issues of the person you were replying to. And I know because I'm in a similar position to them.