First, the trailer as shown can only be talking about Khan. Neither Gary Mitchel or Garth of Izar (the two leading challengers for the Big Bad spot apparently) match the attributes of the character depicted in the trailer. This is how to make the Khan story work within the alt-history of the JJ-verse: At some point prior to the first film, Khan is discovered by Captain Pike in cryonic hibernation. This allows the use of "Khan's vengence" as the through plot of the film as the voice-over indicates. The back story needn't go much beyond a basic "We found him. He tried to take over. We exiled/imprisoned him...." Now, consider that the producers have been hinting at a significant death as a key piece of the film. The trailer seems to support this with the memorial service, et al. But, like everything else in the JJ-verse, there must be a twist to it. JJ wouldn't simply do a direct copy of "Wrath...", despite the scenes leaked in the Japanese trailer that would seem to indicate that he is. However, there's a way to have it both ways: Pike is the one in the last part of the trailer (the "wall scene"), sacrificing his life to stop Khan. This would allow us to have our "Wrath..." visual tributes, be enough of a twist so as not to be a direct copy of "Wrath..." AND allow Pike to have a tragic fate just as Pike Prime did. The "consoling" scene with Scotty and Uhura might argue against that (the obvious implication being that Spock is the one to die), BUT could still work in the context of Uhura grieving on Spock's behalf, or for Spock's pain at losing his mentor, Pike.