IMO TLOZ has been at a kind of standstill since OOT(majoras mask excepted). Retelling the same storyline (not exactly, at least lore-wise; skyward sword was also deviant story-wise), reusing many of the same items(fair point), still not adding voiceacting(I'd rather they wait and do it right than to give bad voice-acting by rushing it). As a series, its always been formulaic, but I think it may be just a bit too much so, these days. I agree that they need to find a way to freshen it up a bit (Agreed).
How about a game where Ganon has already taken over the world? (That's pretty much the original TLoZ, Ganon invaded Hyrule and stole the Triforce of Power, everythings pretty desolate and destroyed. ) Like if the hero of time (Not all links are the "hero of time") was reborn too late, or something. The entire land of Hyrule could be sundered, giving it a completely new and unfamiliar overworld. Zelda and all other threats to his reign would have been long dealt with. The world could be devoid of color and life. Zelda wouldn't entirely lose her place in the plotline, though. She'd have ascended to legend, and, through hidden messages in dungeons and overworlds, and tales gleaned from the townsfolk, she could get plenty of characterization, and also take the place of Navi. Link in this game could be tasked with discovering the secrets left behind by Zelda, and gradually restoring the world before facing ganon and attempting to end his reign of terror.
Unlike previous Zelda games, it'd start out dark, grim, and hopeless, but gradually, as a direct result of the players actions, become more colorful and optomistic.. Looking back, and seeing how far not just link, but the the whole world, has come would create an unprecedented sense of player accomplishment and empowerment come the final battle.
Hell, I'd play it.