1) Crossbow (like the one in LCT)
2) Seeker Boomerang (a boomerang that seeks out it's out it's target sorta like the beetle from SS only with it's destination already set before sending, more like the boomerang from the DS Zelda games only different as it needs to be able to reach it's target without hitting a wall. Like, say that there's a switch on a high part of the dungeon that you can't with a normal boomerang or any other normal item where the only way you can hit the switch is by using such an item that seeks out it's target not matter what.)
3) Seeker Flyer (A bird that flies over you that works like a satellite for an overview camera perspective mode in order for seeker items to work properly.)
4) Seeker Tuner (The second piece required for the seeker items, comes with the Seeker Flyer.)
5) An Axe? (maybe)
6) a Spear? (maybe)
That's I can list for now. I would include guns but I doubt Nintendo would ever implement that in a Zelda game. Yes, I think Zelda Wii U should be another steam punk themed Zelda.