I want to see Bill Foster and Scott Lang in the Ant Man movie, here is how I think it would work. Pym is a lead scientist, but most scientists need other scientists in their lab to help them. So Bill Foster and Scott Lang could be there working in Pym's Lab. It could even be mentioned that Scott Lang is a former ex-con and a father of a little girl. Maybe, depending on how much time these characters are given (like how Darcy Lewis got screen time in Thor) his daughter could even show up. There would be no hint at who they are, they would be back up characters like Darcy Lewis, Happy Hogun, James Franco's lab assistants in Rise of the Planet of the Apes, etc. Characters used to show that Pym has friends and colleagues as well as show that he had a life before the movie where he met these guys. Furthermore Since its written into Ant Man, the actor could leave the character of Ant Man for Giant Man and then leave that identity for Yellow Jacket. So those two identities would be left wide open for possible spin offs. Bill Foster could become Giant Man (his own version not him in Pym's costume) and it could eventually lead to his nephew becoming Giant Man down the line what that actor leaves. and Scott Lang could become the new Ant Man. Lang's story could even include his daughter (who becomes Stature) who could even be mentioned or shown in the Ant Man movie. His story could be a switch from Pym's Ant Man, from a damaged scientist to a more blue collar hero/father and family man. And perhaps down the line in Lang's Ant Man his daughter could even become Stature. And who knows, lead into the Young Avengers perhaps? All I am saying is setting up these two early on not only adds friends and colleagues for Pym, and stories that happened before the movie started, but it also hints at the character's futures without hitting the audience over the head, and gives Marvel even more spin offs they can make money on. All this could even start happening while Pym becomes an Avenger or as soon as he drops that identity. At the end of Ant Man 1, lets say, Pym changes to Giant Man and the next summer its revealed that Lang will become the new Ant Man in Ant Man 2. Of Coarse beyond them showing up in the first film the rest is just my ideas. So, who else wants to see Bill Foster and Scott Lang show up in Ant Man 1 along with Hank Pym and Janet?