I myself have rented ALL my spare DICE cards. My level 1 Mylors were all immediately rented and almost half of my Lorna's too. As for Vera and Qid, no renters. xD

Also decided to rent out my spare gold cards and most if not all of them were rented out except for the Gold Foil Legendaries (maybe 50 DEC was too much).

At the moment, I am currently getting 43.189 DEC per day from it. So not really bad than just letting those cards sit out in our collections . xD