Everything you describe is a usability nightmare including "with warnings when transitioning from one to the other". You might not use any web applications but

Everything you describe is a usability nightmare including "with warnings when transitioning from one to the other". You might not use any web applications but major web applications are the most used sites on the web. Would it not be better to provide full functionality and simply use better sandboxing to avoid spying and nasty stuff? Reducing functionality is like throwing the baby out with the bathwater -- you really want better privacy and more control but rather than attack that problem you want to take the web back 20 years. That's a solution but it's not a very good one. I personally don't think that browsers shouldn't leak all the information that they do -- that should be a hole to be plugged.