more than one doll. I know it's pretty expensive to develop a new body type. If he gets going with the Batman line, he could use a shorter male for The Riddler too.
I can understand why he doesn't want to do licensed characters so much. The wait for approval is excruciating! I do think I read somewhere that he might do his own versions of some literary(?) characters, and taking them from books instead of movies would be a lot easier and more open to interpretation. There are several famous couples that I wouldn't mind seeing him make.