> Force each company to offer two plans (legally): one free + (ads / tracking), one premium (no ads / no tracking), then see how much people care about their data.

I like this idea but only if you force companies to price the non-free version no higher than the actual monetary value of the data they collect. Otherwise you'll have Gmail's "We'll stop reading your private emails" plan priced at 100,000 a month. I don't want to create a situation where only the ultra wealthy can protect their right to privacy.