Looking for in-browser HTML/text editors

I've asked this in a few places, but completely spaced on asking it in
here...the most logical place for this question...

We're building an in-house CMS for our organization and we're now needing to
pick an inline HTML editor for our admin tools. There seems to be more
browser-based html editors than there are CMSes. I'm looking for one that
would (ideally) provide these features:

a) works in IE6/PC (though other browsers are bonus)
   on the front end, .net server model on the back
   end.

b) allows for admin-defined tags/CSS classes

c) allows admin's to block certain styling 
   (namely in-line styles and presentational markup)

d) ability to clean pasted text from Word/Other 
   HTML pages. Ideally, this could be a default/
   automated behavior.

e) ability to create a link within the text that 
   links to a file on the server that can be browsed 
   to. (ie, select text >> click MAKE LINK >> select 
   BROWSE >> browse to PDF on SERVER >> Click INSERT
   LINK to make link)

f) Support for accessibility tags via the interface
   (alt tags in images, title attributes in objects, 
   TH tags, ACCRONYM tags, etc.)

I've looked at about about a dozen thus far:
http://www.darrelaustin.com/stuff/htmleditors.html

Most seem to handle a-d OK. e, about half, and very few handle f.

One that I really like in terms of the markup it produces is xstandard:
http://xstandard.com/

It produces true xhtml, and has nice accessibility features like TH tags,
requires alt attributes, automatically creates title attributes, has a
built-in 'screen reader' preview. It's nice. Ironically, the one editor that
supports web standards in its markups requires the ActiveX and IE. Since
we're windows-based and use IE here, we can live with that.

Other contenders are FCKedit and KTML. I really like the output of
Xstandard, but it lacks a bit in UI.

Anyways, before I spend too much more time looking for others, I thought I'd
ask the list if they'd recommend any product based on the above criteria not
already in my list so far. I'm really looking for a 'clean, structured
markup editor' more than a 'wysiwyg' editor (If that makes sense ;o)

-Darrel