The reason we have Courts in many cases is to try and make decisions on grey areas in terms of what has already been decided elsewhere, you can't open-source that because even the judges won't agree.
Single location where people can access fine print and it's revisions (fine print reserving the right to change at any time is such a BS) would make fine print more accessible (you can zoom in, print, etc, and service could monitor for changes and alert you to it.
Argument that one needs a lawyer to understand the contract highlights a problem with contracts. We all could use education and discussion about contract clauses and analyzing contract clauses online would be a perfect forum for that. It would also put pressure on contract writers and companies to make them more reasonable and clear.
Once fine-print is published we could have a review sites (similar to fact checking sites) that could extract the essence from the fine print and point out major points, issues, etc.
Another, solution that would dis-incentivize 'kitchen-sink' contracts would be ability to invalidate whole contract if one of the clauses is found invalid.