I passed your post on the whishlist section and I plug in shamelessly.
Styling basic tags could be cool, and we also could be presented a style guide page when we create a new site. On this page, will be placed all the common tags, and we could wtyle them and duplicate them to make variations.
It could start as something like this: http://startup-styles.webflow.com/
This page could be published or not, could be used to show the style guide to the client. I always build that sort of page, usually in a fake node post, to simulate all the "rich text" possibilities.