Stuff I know will happen:
Info on new Assassin's Creed game.
Info on Super Mario Odyssey.
SW: Battlefront 2 info (where we find out how many of the new features will actually be paid DLC! )
Stuff I'd like to see:
Days Gone update.
Senran Kagura: Peach Beach Splash western release date (actually I'd like this before E3, since Takaki already said it's coming west this summer).
Senran Kagura: Shinobi Refre info (tentative title, could also be Shinobi Refle. Anyhow, this is the download-only Switch game announced recently).
Fallout 3 and New Vegas HD Remasters for PS4 and X1, with mod support.
Fallout 4 Ultimate Edition (so I can finally play the DLC)
PS4 and X1 port of Dissidia Arcade (about time they officially reveal this).
Final Fantasy VII Remake info and release window for part 1.
Armored Warfare announced for PS4 (already know this is coming eventually, Sony accidentally posted the beta version on the PS Store back in February).
Info on Kingdom Hearts 3 and new trailer.
Unlikely stuff I'd like to see:
New Obsidian-developed Fallout game.
Info on Senran Kagura 7 (game was teased at the end of SK: PBS in Japan).
PS4 remasters of Senran Kagura Burst, Deep Crimson, Shinovi Versus, and Bon Appetit.
New non-spinoff mainline Pokemon game developed with the Switch as its main platform (already rumored to be happening, and I WILL BUY THE CONSOLE FOR THIS IF IT'S TRUE!)
New trailer for the Resident Evil 2 Remake.
So, what's on your E3 2017 wish list?