Johnny Cage's story needs a new direction, but he's not boring. I think he's got a lot of personality, a good number of moves, and he's different enough to always stand out from the crowd of other characters.
Liu Kang, yeah I agree. The only time he was interesting was MK2. But he never changed since then, and was always the character for cheap bastards. I don't miss him.
Other boring characters (not counting small role fighters like Hsu Hao) are the Special Forces, especially Jax. His role's been reduced, so now he's basically Sonya's bitch.
