I'm an avid Destiny player and I've been excited for D2 since they announced it earlier this year, so I was glad to see some of that. They also revealed the Destiny 2 beta dates during E3, so that was exciting, though it wasn't actually during the major conference.
I'm also excited for Monster Hunter. I gave up on the series when it went to handheld-only on 3DS. I just didn't have as much fun with the game as a handheld as I did on my screen, so it's awesome to see it coming back to a console -- and a better one, at that! No offense Nintendo, I love you, but your consoles aren't powerful enough for super serious big games.
And the HZD expansion, as well. Horizon was literally one of the best games I've played in years as a standalone, complete story and plot... I'm excited to see where it'll go from here.