There is no chance that they would use Khan again in the next film. That would be ridiculous. They just showed him asleep at the end to suggest he could still be a part of Trek in the future but I doubt we'd see him again in the Abrams franchise.
The next film will be an original story but it may involve the Klingons aswell as Abrams has been indicating that Klingons are posing a threat, I think they will feature in the next film. The Enterprise has taken quite a beating in the last two films in the next film would like to see it dishing out some beatings of its own.
How about this for a scene in the next film:
The Enterprise responds to a distress call from a planet. The Klingons are on the surface and attacking the inhabitants. Kirk wants to lead the away team but Spock politely reminds him that its too dangerous for him and his place is on the bridge. For once Kirk agrees to stay and lets Spock take the landing team (showing Kirk has become more mature and listening to rules now).
After a few minutes, Spock contacts the ship to tell them they have come under heavy fire from the Klingons and they are pinned down and that two officers are already dead. Kirk tells the bridge crew that he cant stand by any longer and proceeds to beam down. Sulu points out that he should stay behind but Kirk tells him that he cant do nothing while his people are in danger. (This shows his care for the crew). Kirk takes another crewmember down with him. Ensign Evans (Yes this is Charlie Evans) in this universe he's a Starfleet officer and a new addition to the Enterprise, he hasn't got any mental powers yet). He would be played by a young handsome actor and would flirt with Carol Marcus to Kirk's jealousy. Kirk and Charlie would charge their phasers as they prepare to beam down to the surface. Sulu is commanding the bridge while Chekov reports that he's picking up strange readings just as a massive ship decloaks in front of them. Chekov reports that it's a Klingon battle cruiser. "My god!" says Sulu and tells Chekov its time to find out what the new enhanced weapons can really do. It would then cut to a massive space battle between the Enterprise and a powerful Klingon battle cruiser whilst on the surface Kirk, Spock and others take on the Klingons in phaser fire and hand to hand combat.
It would be good to introduce some new alien species and another clever idea would be that a side affect of Kirk being revived through Khans blood would have enhanced his physical strength proving him able to physically compete with Klingons. Not sure if this would be permanent though. Also Kirk is still trying to romance Carol while competing with Charlie but then Kirk also meets a woman belonging to the new species they encounter.
Charlie may or may not become evil in this film but he may encounter aliens in this film which give him new powers which will corrupt him and make him evil for the next film.
What do people think of these ideas??
As long as we get to see a decent
space battle with the Enterprise and some D-7 battlecruisers, I'll be a happy man. I'm not keen on the idea of Kirk being enhanced with Khans blood though