Yes, Harley Quinn as a Joker copycat is a good idea but her appearance should be short and nothing involved with the plot, it must be just a demonstration of Batman's fighting against the crime (and running from the Gotham police dep. ;] )
The Riddler is such a character Nolan can perfectly use for a "twist-ful" plot.
Nobody would be hurt if Penguin and Catwoman is in the film, like I say for Quinn, just for demonstration purposes.
Scarecrow & Ra's haven't been in any Bat-movie in the pre-Nolan era and with them Batman Begins worked great. So I'm open to new villians. My biggest wish is a good plot and a good twist like in The Prestige because I'm going to theatre for the story and so far Nolan hasn't dissappointed me. So I expect his choice will depend on the story, not on the popularity of the villian.
The Riddler is such a character Nolan can perfectly use for a "twist-ful" plot.
Nobody would be hurt if Penguin and Catwoman is in the film, like I say for Quinn, just for demonstration purposes.
Scarecrow & Ra's haven't been in any Bat-movie in the pre-Nolan era and with them Batman Begins worked great. So I'm open to new villians. My biggest wish is a good plot and a good twist like in The Prestige because I'm going to theatre for the story and so far Nolan hasn't dissappointed me. So I expect his choice will depend on the story, not on the popularity of the villian.