Yes you can manage the includes from within Couch (using global editable regions of type 'textarea' and 'no_xss_check' parameter set to '1').
However you said -
..Which would save me editing things in code format.
If by that you mean you'd like to edit the includes in HTML (richtext editor) format, that would be problematic.
The reason being that the includes, usually, are incomplete sections of HTML code. They make sense only after being combined with the rest of the page and the other includes. If you try and use the wysiwyg editor with incomplete HTML portions, it will try to set the HTML right by adding the missing closing tags. This, of course, will mess up your page.
Hope I was able to make myself clear.