I'm not sure this is anymore valid with inline editing, but for completeness...
Looks really nice. Perhaps a good candidate for the HTML editor side would be BUEditor. I think that module has enough usage that it could merge into core and get the benefit of some extra love.
Given the demonstration I just saw from webchick on YouTube (http://www.youtube.com/watch?feature=player_embedded&v=a53Wcq31LmY), to me the Aloha editor seems like it would a much closer fit (http://aloha-editor.org/).
It supports plugins, which would make it possible to add on the Drupal specific functionality, like changing text formats, for example.
#2: please join the (very lively and lengthy) discussion at #1580210: Figure out what WYSIWYG editor to use regarding WYSIWYG editors :)
This issue is more about the UI we provide for the WYSIWYG editor (choosing a WYSIWYG editor does not imply that we need to use *that* UI!).
This is now over at #1702256: Finalize and user test WYSIWYG toolbar designs :)
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