I want to develop a webpart that allows editors to amend its content using the built-in rich text editor, and then display that content in a nicely formatted way. The built-in content editor webpart isn't sufficient because I want to wrap the content in hardcoded HTML so as to enforce my site's graphical design. Also, I would like the web part to potentially contain more than one editable area, and the standard Content Editor webpart only has one.
My ideal would be a visual web part with a predefined HTML layout, with some editable "content areas" to allow modification in edit mode. When the webpart is saved it will just render its content areas as HTML. I have tried using
<SharePoint:RichTextField> blocks in a visual web part ascx template but I don't think this is correct. Can anyone give advice?
One thing I didn't specify was the requirement to add this web-part multiple times, anywhere in the user-editable parts of the page, on an ad-hoc basis. This requirement seems to me to preclude custom-HTML-column-based solutions, but please show me if I'm wrong. I ended up writing my own web-part to solve this problem, see my answer below for that.