What made Crysis 1 great was that every level was memorial in its own way which made the game looking awesome. I am sure it already has the open world open cool looking gameplay. It has a pinger which is a also a good start. I would like to talk more but I will get straight to the point.
A variety of pingers levels and a big boss battle is exacly what Crysis 3 needs. It would be awesome to get the emotion of saving New York from a big flying enemy mother ship in the final level. It would make the game more memorial for the players and successfully.
If Crytek chooses to ignore this from my post, it would hurt their sales. This is a must for a Crysis game and I would like to see it happen.