I would LOVE IT if I could select a block of text and apply a custom style attribute to it (i.e. style="mso-hyphenate:none"). For example:
  1. Select a block of text
  2. Enter a custom style attribute into the settings dialog
  3. Selected text is wrapped with <span style="[style attribute]">[selected text]</span>
It would also be useful to add a checkbox option that applies the style to the entire paragraph (i.e. so the attribute appears in the <p style=""> or <h1 style=""> tag instead os in a <span>).