I actually don't care how much effort it is to implement something, if that something can be fully agreed to.
however, your example is exactly what I feared it would be.
you want someone to appoint themselves the arbitrators of what cookies should be allowed and what ones should be blocked (either by name or by server)
I have _no_ objection to people creating such lists and allowing users to opt to use such lists.
however I have a very strong objection to building such blacklists into the application by default.
the history of blacklisting should prove this. if blacklists were so obviously good and infallible they would be built into every mail server and every mail client. they aren't (although support for them is common in mail servers), precisely because different people have different opinions on what should be blocked.
firefox already _has_ extensive privacy features, they just aren't configured the way that you want to force everyone to have them configured out of the box.
firefox has per-domain controls over cookies (to deny cookies from that domain), all that someone would have to do is to pre-populate that file, no mozilla programming time needed.
as for the 215 hits on "privacy", I don't care how many ideas there are, or how hard to implement. what I want to know is if they are something that _nobody_ objects to (not just none of the privacy advocates object to)