-In the US, it would probably be Washington DC at the Metro Area level in terms of appearance, but NYC in terms of living/lifestyle. Perhaps SF or Seattle on attitudes.
-In Canada, it's generally more European as a whole. Montreal is probably the most ostensibly so in terms of lifestyle, Saint John's NL or Quebec City in terms of aesthetic.
-In the Caribbean, Havana and San Juan would be the strongest candidates that I can think of.
-In South America, Buenos Aires, Cartagena, Cusco would be leaders, along with likely others I am not as familiar with. Sao Paulo perhaps on lifestyle/demographics but not aesthetic or attitudes. There are probably others in all these areas that fit billing, but there always will be.
-In Mexico/Central America, Antigua (Guatemala), Mexico City and some surrounding places, and Merida may fit billing.
However, there can only be one absolute winner, and that is Guanajuato, Mexico:
http://monipag.com/claudia-dozias/wp...017/01/gua.jpg
https://elsouvenir.com/wp-content/up...anajuato04.jpg
https://www.turimexico.com/wp-conten...to-832x500.jpg
http://www.cityclock.org/wp-content/...City-Clock.jpg
https://farm6.static.flickr.com/5689...55f6b5fa_b.jpg
http://www.lugaresmexico.com/ewExter...nio%CC%81n.jpg
http://myartguides.com/wp-content/up...4-1024x785.jpg
I think this rivals the most beautiful historic towns, anywhere in Europe or the world.