When I retired we considered a number of places in the world. Ended up in Victoria BC Canada. Moved there from Vancouver because the weather is significantly better and house prices are significantly lower. But as a place to live the west coast of Canada is hard to beat.
Vancouver would be ideal with a couple of drawbacks. First housing is ridiculously expensive compared to just about everywhere in the world. NYC, Sidney and a few other places are more but there are very few places that are as expensive to live. We are selling a two bedroom 1,000 square foot condo in downtown Vancouver at the moment, ask is $750,000 CAD. This is mid to lower range for that size. A few years old and could use some updates. Detached house is $1,000,000 plus for entry level. Prices go down as you move out of the city but so does the attractiveness of the commute.
Second, while there is an international airport with direct flights to just about anywhere you want to get to, nothing is close by. Seattle is close by air and surface but after that you are looking at significant travel times to get anywhere. Not as bad as Australia, but... If you are used to European travel times you will be surprised at how long it takes to get anywhere.
The cold water diving nearby is world class. Arguably the best in the world is a few hours away on northern Vancouver Island (Browning Pass). I occasionally see divers out my front window. However, the diving in and near to Vancouver is not as good. Vancouver is on a river delta so you need to get off the delta to find anything worth doing anything but skills refreshing. Get out of town and it is much better. A minor drawback but there. Local Victoria diving is MUCH better.
Access to warm water diving is reasonable. There are direct flights to Manilla, about a 10 hour flight as I recall. Indonesia is two flights. Vancouver to one of the hub cities (Hong Kong, Beijing, Tokyo, Taipei) and then a second flight to Jakarta or Bali. Caribbean is slightly closer.
Vancouver is a fairly large city with all the amenities you would expect. It has excellent health care with a university research hospital (UBC) nearby and other world class health facilities also nearby. Education is also pretty much as good as it gets. Both public schools and private are accessible and very good. Two world class Universities are in the city. UBC and Simon Fraser. UBC has a medical school and law school attached and has a pretty good reputation in a number of disciplines. (Full disclosure I did research and taught at the UBC faculty of law for a few years.)
There are three ski hills that you can see from downtown, and Whistler/Blackcomb is a couple of hours away. Hiking, fishing, boating, pretty much any outdoor activity you might want is nearby. Vancouver is on the ocean at the foot of a range of mountains at the mouth of a large river so everything outdoors is nearby.
Vancouver is a multicultural city with several significant Asian communities. Walking the streets of downtown you will hear many languages. Restaurants serving the cuisine of many cultures of the world are available. Safe as it gets - while we are near the US the gun culture rarely crosses the border. I don't know anyone on this side of the border that owns anything but a hunting rifle - and those who do are hunters.
