I want PH on Wii, cel shaded like WW, even if uses the GameCube controller. They should do ports between platforms. Nintendo designs a new game for DS or but doesn't port it to Wii, they lose out on sales. The cost to port and re-render is much less than a new game development.
As for new concepts, its about time they went with some new macro themes (large scale). How many more times do I have to kill Ganon? Always with the Triforce and the same Master Sword? This is where I think WW was SO fantastic because the landscape was massively different and unique, but still tied in with prior macro themes. How about a new antogonist NOT named Ganon? How about some other bad wizard, other hidden secret powers (like the power of the very Earth itself being tapped and drained of magikal energy) so the antogonist travels between time and dimensions to gather the elements needed to pentrate the fortress of New Bad Guy who is sucking the planet dry. Do a swerve on it: Bad Guy is sucking Hyrule dry to save his other world in Other Dimension, because over there his world is dying from an unknown malady. Bad Guy Wizard isn't really "bad", just bad for Hyrule. For his world he's a savior. After antogonist finally penetrates Bad Guy fortress and having gathered the strength to do so in Hyrule, instead of killing Bad Guy Wizard he banishes you off into his Planet/Dimension to get you out of his way. To get back and to ultimately save Hyrule the second half of your adventure is to actually solve the primal malady of their Universe (I'll leave it to the Zelda designers to earn their paycheck and figure out whatever malady that might be). Two games in one.
Or swerve it even more: You change protagonist when Link meets up with Bad Guy. You fight and "defeat" him, but not kill him. He tells you his story and emplores your help, as clearly you are a capable hero. When he send you into his world you "take" the body of some other being, maybe a girl (become Zelda?), maybe a magic user, something cool and different. You are still You, but your form changed (not unlike the wolf in TP), but to a more versatile character than the wolf. Becoming Zelda might be cool, but not a swords-woman, maybe a magik user or a stealthy-type thief-type. (For anyone who thinks that a female protagonist doesn't sell, check the best selling computer game of its time, Kings Quest 4 in 1988 -- before most of your time perhaps).
Just some ideas.