Really, we've done this alot on this whole forum. Before all of this rapid Spirit Tracks news started coming out, Zelda Wii was really all we discussed. So I've already spoken my mind enough, however, I will give a short response in what I want in Zelda Wii.
I want a better attempt at a darker tone.
TP was not as dark as advertised.
I want Nintendo to get creative with Wii Motion PLus, but at the same time, don't get carried away and add things in the game just because they can. (For example, please don't make us use the Wii Balance Board)
I want more interesting characters.
I want an engaging storyline, with the dark tone mentioned above, and I want to care about the people involved.
I want a badass villain whom I am motivated to go defeat.
I want voice acting.
I want something more than the generic dungeon-to-dungeon formula with the one plot twist in between. Include multiple plot twists and maybe some mini-dungeons and more non-dungeon missions. Not that I don't like the dungeons, but I just want more.
Speaking of dungeons, i want more unique and difficult puzzles inside the dungeons.
I also want more unique boss battles.
PH did this very well, if you want an example.
More sidequests with useful rewards.
Epic music.
More unique items instead of just the generic bow and arrows, boomerang, hookshot, etc.
More threatening enemies and bosses.
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In sum, I want the game to be more
unique than previous titles, more
difficult than recent ones, and a more
epic and engaging storyline than previous games. Hopefully, Nintendo is not afraid to do these things.