Ah, where to live in this big world. I contemplated what I wanted in a city and came up with a short list. English speaking, beach, sub-tropical, big city. Came up with LA, San Diego, Honolulu, Miami, Sydney, Perth, Brisbane. That was about it. I now live in Sydney. Great place but a bit far away from Canada.
A lot of Canadians move south to escape the long, cold winters. They go to Florida, California, Texas, Arizona and New Mexico. If I were an American and were considering Vancouver I would prefer to live in or around Seattle. Slightly better climate and it is still America. Changing one's citizenship is a huge move. In Seattle you are close enough to Vancouver and can drive there in a couple of quick hours. I would check these out before any move across the border. You have Bellingham and other cities to choose from. Portland, Oregon is another possibility. So are places like Folsom east of San Francisco. Nice place. Santa Barbara is my pick of California. Very nice place and it would be a great place to bring up children.
I grew up in Kamloops, BC., in the interior. Hot and dry in the summer and definite seasons. A great place to live and bring up kids. Ditto for the Okanagan including Penticton, Kelowna and Vernon. I went to UBC and lived in Vancouver for many years. It is one of the best cities in the world to live in. Beautiful scenery, Mountains in the distance, Beaches nearby, good transit system and the Canadians are generally friendly.
The downside is the loooooonnnng, wet winters. You really have two seasons there: cool and wet and mild and wet. It is sunny in August and part of September. If you love the beach then Vancouver isn't for you. You might want to consider swapping homes with someone in Vancouver. I am sure you would get plenty of offers and then try the place out for a year and see how you go.
Where to live in Vancouver? I like the West End which is full of apartments but is close to downtown. North Vancouver is nice, too, but a bit wetter. It goes something like this: White Rock 30" rain, City Hall 40", Downtown 60", North Vancouver 80" and West Vancouver 120". It is one of the few cities in the world where at times you can go from the beach to the snow on the same day. I love when the snow covers Grouse and Seymour Mountains, both of which have skiing facilities. Living out at Ladner or White Rock is good because the climate is the best there. Modern communities and good amenities.