Re: Next Batman Villain?
Black Mask would be great for an animated trilogy. The Penguin/Black Mask/Falcone mob war with assassins, like Deadshot, Deathstroke, etc etc. That'd be a nice animated movie saga, but big budget, live action... it's too risky and bland for the general audience.
For a big budget movie, Black Mask would be a great secondary villain. But for the primary, you need someone like Joker, Riddler, Mr. Freeze, the Court of Owls. Something like that.
I would use Black Mask's gang as Batman's focus, only to have him find out they're being overseen by The Court of Owls.