Great post and fantastic ideas! I've been thinking a lot about tags and how steemit handles them and these changes would make a huge impact on serving the best content to the right people.

One question for you, regarding the following bullet:

• Each curator can only green-tag up to 3 tags per article. Curation rewards are split between the three, so it may be wiser to green-tag just one tag that very accurately describes the article, than going for three random ones.

Wouldn't you want to gather as much information from curators as possible, instead of incentivizing "strategic" voting?

For example, a post about Pokemon GO would be relevant content for the "pokemongo" "pokemon" and "gaming" tags, at minimum. But the most relevant tag is "pokemongo" so all the savvy users would upvote only that tag, leaving the content unavailable to users who haven't expressed explicit interest in "pokemongo" but might be interested based on their interest in "pokemon" and "gaming".

Sorry if I missed something that counteracts this incentivized behavior, looking forward to your reply. Thanks again, it was hard to find anything I didn't immediately agree with. :)