That approach could have some random unintended consequences. I shuffle my playlist and listen to a few tracks. One comes on that I don't like or doesn't match my mood, so I peek at the playlist to find on that does match my mood and double click it to start it playing. Unbeknownst to me, iTunes triggers a reshuffle when I do that, and the very next track to play is the one I was trying to get away from.
The better solution (at least from my perspective) is to not pretend that shuffle is a setting, but an action. Simply have a button that says something like "Shuffle this Playlist" or more explicitly "Re-Shuffle this Playlist". Play, stop, forward, back all would work normally within the existing order (straight or shuffled), and if you wanted a new order, you click the "Re-Shuffle" button.
The better solution (at least from my perspective) is to not pretend that shuffle is a setting, but an action. Simply have a button that says something like "Shuffle this Playlist" or more explicitly "Re-Shuffle this Playlist". Play, stop, forward, back all would work normally within the existing order (straight or shuffled), and if you wanted a new order, you click the "Re-Shuffle" button.