Princess Die ft. Lana Del Rey would be cool. Sometimes I try to imagine how it would sound with Lana's voice. This song is just like especially for her.
I'd love if the ARTPOP cover was shot by David LaChapelle. Sorry, I love Steven Klein, but David is just the right call...and a feat. with Lana would be so beautiful...and a feat. with Britney would also be so cool, not only because I love them both, but also to put an ending to this fan base feud (that I just don't get, by the way...)