Shortly after E3 2013, Shuhei Yoshida of Sony Worldwide Studios commented on future DLC Releases, commenting the game's sale of 1 million units but claiming "it was not enough to have the momentum in terms of a business standpoint to continue to add characters or do a sequel", confirming no more DLC is likely to be released.
Followed by him saying if a sequel would be made the super system would change or something.
That's one thing that should stay. It's helps make the game unique, and it should only take some polishing to perfect.
However, I don't think there should be all the same specials for a returning character.