Alike many people around the world I was absolutely ecstatic when the news came out about "The Incredibles 2" being developed. Personally the film was one of my favorites and I have seen it over 50 times (no exaggeration). I have always thought about ideas to expand upon for "The Incredibles" Universe. It all started with me watching the deleted scenes on DVD. If you have not seen the deleted scenes from "The Incredibles," here's a youtube clip of them down below.
https://www.youtube.com/watch?v=x1qZYxAJkYk
The alternate opening is a great setup for a prequel. You can start with Bob and Helen developing their powers as kids. Bob can be a stud football player while Helen is a fantastic gymnast. The government soon realizes there are many people out there with "special" abilities and begins to recruit them, with Rick Dicker from the first film overseeing everything. All of the "Supers" are then trained by the government to help protect the world.
But back to Bob and Helen, they meet as teenagers while being trained. Bob also becomes close with Lucius Best, a figure skater who almost competed at the Winter Olympics, but could not for obvious reasons. Bob tries to woo Helen, but he is unlucky as she seems to take interest with another guy, Snug. Snug works as a government pilot and is helping the "Supers" train. Another plot for Snug is that Helen did "call in a solid you-owe-me" in the first film. Snug clearly owes Helen a favor and the reason why can be shown in a prequel.
Another sub-plot within the story can be the introduction of other supers not seen but mentioned in the first film. I also dug around a lot with "The Incredibles" DVD and there were even Superhero teams. Introducing these teams can be a great idea to expand upon.
As they continue to train, Bob and Helen fall in love (in secret.) The Superhero Relocation program is soon put into effect and Supers are not allowed to have children, as mentioned in the deleted scene by Syndrome. Bob and Helen also have to hide their children from the government, with Rick Dicker being the only in the government to know of their existence.
There is a big plot hole, who is the villain? I think it could be Helen's ex, a random jealous guy from training who turned bad or Brad Bird's original villain instead of Syndrome, but the villain would try to take Violet. Another idea is seeing Dash grow up too. Brad Bird, just some food for thought.
-JM