This idea isn't for me. It's my colleagues who aren't as into editing emails.
Sometimes when they are working there will be a bit of text for whatever reason (coughcopyingfromwordcough) or using a table, that won't be formatted the same as the other body copy. What would be awesome is if they could select a word that was correctly formatted. Press a button to 'save' the formatting. Then highlight the texts to be updated, and 'paste' the formatting onto that text instead. Font Size, Color, Line Spacing, etc, all easily copied from the correctly formatted text to the incorrectly formatted.
I'd open the HTML, remove the strange formatting, and move on with life. But not everyone feels comfortable doing that, and this would be a super help to those with less confidence.