Why not have a game like red alert, or a some kind of FPS where players from xbox live compete against PSN players. They could have console specific weapons, gear ect. I don't know just a thought.
And for Elder Scrolls 6 retain everything from Skyrim add Throwing weapons (knives, tomahawks, stars), Flails (morning stars), Bring back Fisticuffs. Have a land baron system like in Fable where you can but up all the houses, shops ect. and gain an income. A moral standing system like fable. Have more Types of armor and weapons. Become a Jarl of a city and have to rebuild it, and run it sort of a Dark Cloud style. Multiplayer (at least one friend). Have a dog companion. (seems to be the trend). The dog can be another skill tree and have different breeds). more bizarre types of enemies and have more enemies is the water and sky. Swimming in the ocean in skyrim might get you a slaughterfish or two. Where is the sharks, or a kracken? just roll some random pictures.