I was playing around with this card in a prerelease today to some interesting and semi-impressive results. It got me thinking. Doom Desire is a potentially deadly attack. Not only does it instantly KO, but it does so at the end of your opponent's turn, meaning they will have to replace their active before your turn begins. Of course this can be nullified if your opponent retreats / uses Switch / Rush In / whatever. Dralgalge FLF could serve as a possible answer, in conjunction with Hypnotoxic Laser. Silent Lab would be your stadium of choice to block Keldeo's Rush in and Virizion's Verdant Wind. Switch is still a problem, but the chance that your opponent can play one every turn is low. Bronzong would allow for energy acceleration, since Doom Desire does require two energy that must be discarded.
All in all, I don't know if Jirachi could actually be competitive, but I can see some potential. If nothing else, it would make a nice "for fun" deck. I'm not saying this would be any better or worse than current Metal decks, and I'm afraid it could get a little clunky as well.