[CyberFonic]

In order to be employed by a USA company the employer needs to file several forms for federal and state taxation, insurance, etc. These forms require a SSN and relevant authorisation to work in the USA. I fail to see how living in Canada and not holding the appropriate permits that any employer would want to go through all the trouble of hiring you.

As you have found, contracting is probably your only option if you want to work for USA companies and even then you might benefit from incorporating in a suitable USA jurisdiction.

In my experience, the amount you are paid generally reflects the cost of living where you work. Although you might earn far more in SV or SF, your living costs will also be much higher. In the long-term you might not have been able to save any more money.