I'll try to answer...I'm a second year student at UBC.
The city I think is awesome, I enjoy Vancouver a lot. The bus system is pretty good, it's easy to get around from the UBC campus to the surrounding area to downtown and stuff. Not to mention it's so close to Whistler. The atmosphere I really like, I lived in LA for a year, and the people here are so much nicer and less..."judgy?". The weather I can't really comment on, I'm from Oregon which has almost identical weather, I'm used to the rain, but some people get depressed by it raining a good portion of the winter. The school academically is great, it's ranked high, and so far I've had good professors. In my faculty at least (Science) though, class sizes are big ~100-200 people. I don't know anything about sports, I think UBC sucks at sports, I don't really know though. Parties are always present, it is a college after all, and the 19 year old drinking age is awesome. Tuition isn't that high, but it's not cheap. I think it works out to 19,000 a year, plus cost of living (housing, food, etc). Cost of living is somewhat high...Rent you should expect to pay ~600 a month, give or take. Food and drink is way more expensive than I'm used to here too, a nice restaurant dinner is like 15 bucks, plus tax, and the taxes here are pretty high, 15% on stuff you have to pay full tax on. There isn't enough housing on campus for people to live there for 4 years, but it's very close to residential areas where it doesn't seem to hard to get an apartment or room or something (based on looking around craigslist and the AMS rent site). There are lots of people from the states. There are lots of cool people, and lots of skiers. Though, if you are studying science like I am, be prepared for everyone in your classes to be asian, haha.
Anyways, I realized now that's just one run-on paragraph, but hopefully it helped. PM me if you have more specific questions.