From microsoft: Gameplay for all the games coming out after e3 (recore, Gears, crackdown, scalebound, etc) announce new games.
Nintendo: NX and zelda release date (NX at least release window), new metriod (2d one for 3ds and new prime for NX) new ip and unexpected things like new F-zero.

Release dates for Valkyria Chronicles and Valkyria chronicles:sure revolution for Europe, also English trailers for both.
Some more SOLID news on final fantasy 7 and good gameplay footage.
Danganronpa 3 news and gameplay footage
News in DONTNODS new game as LIFE IS STRANGE was just purely incredible
Horizon Zero Dawn release date

Saint's Row V announcement.

Soulcalibur VI announcement and a return to high levels of quality.

Fallout 4 DLC announcement.

Borderlands 3 announcement which will be epic.

WWE Xtreme announcement. The guys and girls of the WWE are sent to an island paradise for photo-shoots and general relaxation. Teaser video has John Cena and HHH trying to bounce each other off a platform in a pool while using only their butts and wearing Speedos. Vince McMahon watches at pool-side with a big smile on his face.

-NX release date for holiday 2016 with good 3rd party support
-Zelda Wii U announced as a launch title for NX
-Super Mario 64 sequel announced for NX
-Paper Mario game similar to the first two announced for NX
-Pokemon Gen 7 announced
-Console Fire Emblem announced for NX
-Red Dead Redemption 2 for PS4/NX
-Valkyria Chronicles Remaster and Valkyria of the Azure Revolution localizations
-Dragon Quest Builders and Dragon Quest XI localizations
-Danganronpa 3 localization

I want Nintendo to really go all out with a LoZ themed event at E3 this year.

I'd like to see the series as their 1st movie planned now that they have a business agreement with Universal Studios.

I want a TON of Zelda Wii U footage released as well as the title for it and a release day (not season or month).

I'd like to see the Symphony Of The Goddess there again.

I'd like to see Zelda Williams there to help promote it as well as mention a specific NPC found within the game.

I'd like to see the Legend Of Zelda NX tech demo.

I'd like to see Monolith Soft's next project (yeah, more than likely still a bit too early).

I'd like to see Retro's new game.

I'd like to see the NX announcement.

I'd love to see Samus' next adventure in a mainline Metriod (c'mon Nintendo).

I'd like to see Xenosaga HD.

I'd like to see Bayonetta 3 NX.

I'd like a Platinum Games second party announcement after all current games for other platforms are finished.

You know, basically stuff (besides NX) that should have happened by now.

Something to convince me to buy into VR.

My list of things I want to see seems WAY more plausible, lol.

The new 3D Mario game, Zelda U, Paper Mario NX, Banjo Threeie, new Crash game, new BioShock game, Left 4 Dead 3 and Red Dead Redemption 2.

like when they announced bloodborne and LBP3 less than a year from release?  They have a lot of stuff far away but that's only because we already know all the stuff that they're releasing soon and they usually have a nice November or within a year surprise more so than the other 2.

something that is basically impossible to show at a conference?  check