On the Doctor Doom side of things, there’s currently a Doctor Doom movie in development, with many fans also assuming that the character could enter the Marvel Cinematic Universe at some point as the Disney-Fox merger finalizes.
As far as opportunity goes, although he’s just chatting possibilities in his conversation with JoBlo, there’s still time for Nicolas Cage to get his hands on one of these roles.
For The Joker, DC is currently in the process of developing an origin movie showing how he turned into a grinning maniac; Joaquin Phoenix is circling the project, but he has not confirmed his status as the new Joker, and there could be room for someone like Cage to move in.