I'm obviously a Nintendo fan, so I will just speak about what I want from them.

For Nintendo I would love to see:

(Disclaimer, I am going to use videos to get my points across. By no means do I want the videos to have any of the same art direction, continuation of series, or graphics. These videos were chosen to express the type of CONTENT I want in the trailers in the next E3.)

- Legend Of Zelda: We know there is supposed to be a playable demo, but due to the fact that the odds of me being at the next E3 is practically 0, I want the Zelda trailer to contain a story trailer, obviously with some gameplay. 

Example 

(Obviously I know this is not the art direction they are taking, yet again I would like the content of the trailer to be similer. Having a good look at both CG and gameplay with a hint of story.)

- Metroid: I've always thought these commercials were the best Nintendo had to offer, I love the live action mixed with CG. They wouldn't even have to show me any gameplay at all, keep us guessing for all I care but keep giving us these EPIC trailers!

Example

(With this, note I am not asking for another Metroid Other M game. Though I MYSELF would not mind. I actually liked the game.)

-Star Fox: This I want sheer gameplay, sorry Fox, your stories in your games are pretty weak. Not terrible, but we do not pick up Star Fox for the story.That being said I would LOVE to see them push the graphics on this game and give us some breath taking space backdrops to explore in our Arwings. Let's make it happen Nintendo.

Example

(Obviously graphics that will drop a few jaws, content purposes only again.)

Other than that, show the updated graphics of The Devil's Third, announce Fatal Frame, show SOMETHING on Shin Megami Tensei X Fire Emblem, announce the console version of Pokken Tournament, show some tweaks you've done to Xenoblade Chronicles X if it hasn't released (and honestly, it should be released befor then), and you can call me a happy consumer.... Till next E3.

(EDIT) OH, AND FOR THE E3 SURPRISE MEGA TON:

Megaman, 3D action game with the graphics of this:

Exclusive to Wii U.

How about Nintendo get some third party games? That seems to be their biggest drawback.

Maybe Animal Crossing?

I feel you, but I'm trying to be as realistic as possible. From what I KNOW is coming out, what would get me the most hyped. Saying anything like Arkham Origins would pretty much be unrealistic by now. I don't know.

I guess a game from a third party I would LOVE to see a return of is a new Crystal Chronicles for Wii U, it could happen. Chances..... Not good at all. Oh, and edited surprise third party megaton game with Megaman.

I won't say no to anything. I know there seems to be a really big fanbase for the game, but being I never played them I couldn't comment on it.

I agree with all points, but also :

A Kid Icarus Game , unlikely, but whatever

Another new IP that gets a lot of attention just like Splatoon.

SMG x FE. - Epic, big, and vast trailer.

Kirby Platformer for Wii U.

fully 3D open world Pokemon that isn't a offshoot or spinoff. Then watch the gaming universe explode.

I hope level 5 continues the professor layton series on wii u or the new 3DS (instant buy)

COMPLETELY agree with how they should present their Shin Megami Tensei trailer. There are going to be a TON of characters in that game, so it should feel massive. Would you want a SRPG or a JRPG style game? I'm still trying to think what formula would work  the best for the crossover. I think SRPG.

Without a doubt, the only problem is I really just don't see Nintendo doing this. Keep the faith though! 

I'm just personally trying to keep my expectations in check to a degree. though I did add a surprise Megaman game to the mix...