Remember Dr. Cho's machine that created the Vision android? Yeah thatss the set up for creating a Thor clone. Antman showed us that giantman is not far behind as Dr. Pym is about to make a break through with the Pym particle at the end of the movie (he is clearly contemplating going into the microverse to save his wife, also they made an ant into a dog sized creature), so Giantman will be possible. After Hulk's rampage and the uncovering of the Hydra plot from the Winter Soldier movie, all Avengers could easily be painted as terrorists not just Cap. As for how closely they are following the Ultimates storyline? They are doing the Iron Spider sub plot so why not others?