#6 Zone of the Enders
Hideo Kojima teased a third entry to this often under-looked series in 2012, but the team behind it has since disbanded. Kojima's entire focus has instead shifted to Metal Gear Solid V: The Phantom Pain, and as a result the project was sadly put on hold.
While a majority of Kojima Productions' fanbase is no doubt greatly anticipating The Phantom Pain, I think it'd be the proper course of action to see the company edge itself back onto Zone of the Enders 3 once the new Metal Gear is done. I imagine ZOE3 would run in 60 frames per second and feature more of the high-speed aerial combat of its predecessor while introducing more playable characters and less escort missions. Heck, one can only dream of what an open-world Zone of the Enders game with No Man's Sky-esque planet-to-planet traversal would be like.
