GreaseMonkey as a form of web-design vigilantism has two problems: 1) The web is too large and too messy a place for GreaseMonkey's fix-the-web-one-site-at-a-time approach to be practical. We need an subscription-style approach à la AdBlock. 2) Multiple user-submitted redesigns exist for the same site. Yes, choice is great. Especially if you're a power user. But it's confusing for my grandmother who has neither the inclination nor the time to weigh the advantages of different mods to her favorite recipe site. Again, AdBlock has the answer with its you-don't-see-me-but-I'm-making-your-life-better mindset.
So what about this: create a collaborative community for web cleanup. Members with an interest in improving a particular site will act as curators, creating and maintaining a single, cruft-free redesign of that site. These redesigns will be transparently applied to sites of any end-user who chooses to subscribe to this service, thus requiring no effort beyond the initial installation of a browser plugin.
Playing devil's advocate here, I'm sure the top issue to be raised will be: What guarantees that sites won't be altered in an unfavorable or, worse, biased way. Technically: nothing. But then again, what guarantees that wikipedia articles stay accurate?
Thoughts?
PS: There's something called GreaseFire, but that only informs users that userscripts exist for the site currently being visited. The task of manually evaluating and then installing them is still left to the user.