The flat coloured version when done in red is incredibly effective I think:
I think this one will definitely be going up on Redbubble. As regards the gold background, I think the gold on black will also be going up, but I've also been trying to come up with alternative backgrounds. i came up with the following:
Possibly a bit obnoxious or OTT?
Slightly tweaked version of the one above.
Or I could just go the full-on romantic route and opt for pink clouds:
Of course, I could just upload all of them and see what sells, but I welcome people's comments!