Fascinating choices, Anthony, especially considering that you have made them without ever having been to these countries.
For North America, I would choose Mexico over Canada, predominantly because of the climate. I have spent some wonderful time in Mexico City and I look forward to returning.
In South America, I think Uruguay is a decent choice. Montevideo is like a mini Buenos Aires, which is a most wonderful city.
Europe presents a challenge for me. The places there that I love tend to be further north: Netherlands, Denmark, Sweden, France, Germany, Belgium. But their climates are too cold for me in the winter, except for the possibility of the south of France.
I have been to about twenty countries in Africa, so that gives me a little bit to work with. Of the places where I have been, Senegal offers the most stable political environment. I have been to Dakar, its capital, several times, and I can get by in French, so that helps.
All righty, then: Asia. Singapore would be a better choice for me if it were not situated as close as it is to the equator. Too hot and humid for me, though by all other measures, life could be very comfortable there. If it weren't for the weather, I would probably choose either Istanbul or Tokyo, which I are two cities I have enjoyed visiting.
Your Oceania choice of New Zealand is a good one. I totally love Jacinda Ardern. I have been so long-winded on my response that I am going to leave it at that.
If you are curious about some of my travel writing, you can find quite a bit of it in the Globetrotters publication, right here on Medium.
Wishing you the best.