One of my first signed songs was "Sounds of Silence" Simon & Garfunkle. At first I just thought the title was appropriate, then as I got into it, I found that you can do a lot emotively with the signs in this song. Especially if you use Signed English as opposed to ASL. Definitely one of my favorites.
I love to sign OTR songs but your restriction on the clear lyrics really throws a lot of them out.
Michael