You are a very long way away from getting a green card (permanent resident visa) for the US. However, if you do go that route, you should be aware that the US will tax your income for life (or for ten years after you give up your green card) even if you decide to leave the US and return to your home country. I made the decision to come here (to the US) long before this was an issue. However, if I were to do it again this would be a major concern on my part.
In my experience job opportunities are better in the US. However, I think that the difference is much smaller than it was when I immigrated to the US.
If it were me, I would be torn between UBC and Northeastern also. If it were only the school, I would probably have a slight preference for NEU. However, given the difference in both the difficulty in immigrating after getting a degree, plus the US tax policies, I think that I would go with UBC. The cost difference also favours UBC. Crime is probably slightly lower in Vancouver also, although it would not particularly worry me in Boston. I also agree that your other two choices are quite good.
When you apply for a student visa, do not tell them that you are thinking about staying after graduation. As far as immigration is concerned for either country you are coming here to study with the intention of going home. Then when you are close to getting your bachelor’s degree you can think about whether you want to return home or apply for a work permit.
The weather is not really the same, but I agree that it is probably equally desirable in either location. The summers are beautiful in Vancouver. The summers in Boston are mostly pretty good, but it will get too hot from time to time. Winters in Vancouver are very wet, but it rarely gets cold enough to snow. Winters in Boston will have some cold days, some heavy snow days, some sunny days, and some of almost everything that you could imagine.
I think that for me the taxation thing would scare me if I were thinking of immigrating to the US now, and would push me to Canada.