It’s just that it had so much squandered potential. A Batgirl and Joker wedding is such a twisted and fun idea and it was all tossed out the window so another character who is not Batgirl could ...

the impending wedding, the Joker’s involvement in turning everything upside-down, and, gradually, the creepy realization that The Riddler maybe has the hots for Batgirl due to her intellect.