Convince me that TinyMCE isn't the way to go

My requirement is that only certain styles and tags can be used in the editor and that these are defined site wide in the CSS. Different instances of the editor might include a subset of the main css so that particular parts of the final pages are consistent e.g. we have an article excerpt on the front page. These all have to have a similar set of styles/classes, then the full article might have a larger or even different set of CSS styles/classes.

As CSS is used throughout the site and not just on those bits that the user can edit via CKEditor, I want to manage the CSS in one place and not have to configure CKEditor should the styles have to change. It seems tinymce just includes the site's standard css file/files so it's only a matter of structuring the css files effectively.

I'm not sure CKEditor integrates CSS as well - or am I wrong?

Regards
Pete