Just an area where members of a site can leave messages to each other but not visible to the public. Eg. can be used for asking admin-y questions about certain parts of the site or asking members to edit a page they are in charge of.

Could be in the form of a forum, or even just a huge editable text box (messages are temporary and can be deleted)

Should be accessible from the admin page.

right now it removes all table formatting, all javascripts, and all <div>s

Instead it should fix repeat <div>s
eg <div><div>content</div></div>

and break the lines and add indenting where appropriate.

Formatting itself should not be removed unless it is repeat.
<div>s with custom id and class tags should not be removed

A few suggestions here:
Allow forms on blog articles. Currently doing this results in submitting the form data to the parent directory.

Allow direct editing of HTML of the form

Inserting line breaks in 'block of text' in forms makes everything below the line break uneditable after the page is refreshed

Typing into a text field in edit mode should set that as the default value for the field.

Include option of presenting data (for radio buttons) as a bar/pie chart under admin (for survey or poll purposes)

minor: Under the tickets section in the admin page allow editing of title of email for notifications.