Very nice Rob,
One thing that could be improved is the position of the Notes ... Append ... drop down menu and button.
Doesn't it make sense to group it next to the Signatures and Personalities buttons/menus. After all, one would choose which note or signature to append to an email, and it would to good to do so prior to working through the block or text.
Please make the change at your earliest convenience
(assuming others agree with my unassailable logic ...)