Chiang Mai, not perfect but almost there..
Got my eye on Cuenca, Ecuador, high in the low 20's, all year long. Low in the teens, at night (I like it to cool off). So, N. America spring, all year long. Easy to get retirement visa if can prove income of something around 1000 USD/month (I think it's a bit less, but let's say 1000, most expats can easily show this number). There are also beach cities in Ecuador with temperate climates, if you need a beach (give me mountains over beach, any day).
Yes, Gran Canaria is also a good alternative, most of the year good weather, and not so humid like here.
And flights are cheap to Europe..
Chaing Mai - I´ve heard from a lot of retired Swiss people there
My retirement destination will have to include a lot of golf courses with said nice weather.
California has perfect weather. You could surf and snowboard in the same day.
South Africa (which is the cradle of man kind) also has perfect weather in most of the country. Some areas up north can get too hot in the summer. Too bad crime is a big problem there.
I was thinking Cali as a potential too but other sorta climate related cons..earthquakes..
I bet there was a whole bunch of dudes just like us that had this discussion many many years ago hoping to find the place.. I'm guessing that was what eventually prompted someone to invent aircon as the answer.. ;_;