To begin, Sapphire Weapon:
That mech we get to pilot is totally bad ass. I'm looking forward to this more than just about anything else in the patch. It's just that cool, holy hell. I'm seriously getting some Trails of Cold Steel vibes from this encounter.
*Ahem* From what I can gather, it looks like Gaius wanted to be the one to confront his child. Likely because the lack of trust anyone has for him, we went instead to face the Sapphire Weapon.
Main story:
Looks like things are about to escalate big time. Seems like the catalyst of the events to come is centered around the crystal tower. Now I'm not one hundred percent sure if those shades of light we are fighting are other warriors of light. However, it does seem like the most likely explanation given Elidibus' plan at this point of time. The fae folk are getting dragged into this mess as well, possibly due to our relation to their king. Going a little further into the trailer, we are now in Eulmore, where we happen to be when the starfall happened. There are several circles that remind me of the trial against Hades, providing further evidence (at least to me) that these may be other warriors of light.
"There may come a day where you forget the faces and voices of those you met along the way." This could mean many things really. Based on the fact it shown Lyna and G'raha during this point of the trailer, my guess is that something will happen that will cause the latter's death. Everyone will forget him after this and the scions are sent back if his 'If I die, you should be returned home' theory is correct. Two scenes later in the trailer seem to suggest this will happen.
The warrior boss and the sorcereress boss are likely other versions of ourselves as far as I can tell. They seem to be more powerful than the shades of light. The dragoon that took down the airship may be another one of these unusually powerful shades of light, possibly another boss. I do have to wonder who Y'shtola is speaking to with the cacophony of voices line? My guess is Elidibus as he is assumingly the one causing the shades of light to appear on the first.
G'raha will fight beside is in a story trial, leading to him being injured by Elidibus. Based on the end of the trailer, this speeds up his crystalization process and perhaps leads to our memories being wiped in relation to the Exarch when he dies from it.
Nier:
Things are also starting to escalate when it comes to the raid series. Robots are attacking the dwarves, forcing them to bring out the tanks to defend themselves. It could be possible that this is 9s' doing as I think he's one of the YoRHa units seen standing against 2P and the dwarves. He's the one standing in the back ground just to 2P's right. Quite a few new bosses that weren't present. They look a lot cleaner than the robots we fought in the previous raid, so maybe weapons the Council of Humanity used on their home base.
My guess is to why these ruins haven't been found is probably the most likely. Perhaps these structions do not exist on the first but as a result of a dimensional merge? We do have to access them through a rather unusual door with Emil's face acting as a lock. I suppose if the mountain was closer to the wall of light, the Eulmorians didn't have a reason to fly over it. We did enter Kholusia from the beach to the eastern side. However, I'm not going to pretend I know what goes through the mind of Yoko Taro.
Bozja:
A lot of escalation this patch. We are going straight to war with the Garleans with the Bozjan resistance. The Hrothgar Paladin shot is interesting and it seems like the battlefield is acting as another Eureka. Perhaps with objectives being important to completing the relic rather than leveling up. Perhaps it is even a new dungeon.