In all honesty, I don't think Incredibles 2 needs its own thread yet. The announcement is still fairly new, and it won't be for a few years until the movie is finished. But I guess this can be a speculation thread...
Considering that Finding Dory was announced last year, ten years after Finding Nemo, I remembering thinking then that there would be a sequel announcement for The Incredibles. I mean come on, if any Pixar movie deserved a sequel, it was The Incredibles. (A sequel to A Bugs' Life might've been the most intriguing announcement, but it ended nicely to start with, so I'm not holding my breath for it at all.) But now I'm making (a joking) speculation that in two/three years' time, we may get an announcement for a Ratatouille 2. Who knows.
The voice actors who played the children have grown up by now, though I don't think that will prevent them from coming back to reprise their roles--they would just have to be older in the movie. But of course, then that makes Helen and Bob older, too, and it makes me a little sad inside to think about it. Yeah, it would've happened no matter what, but it's still sad. But that would most likely be the main reason why they will leave the superhero work to their own children, though I can see them being worried sick about this. I mean, they put their lives in danger, and they are young. I'm sure Bob and Helen's parents worried sick about them when they became superheroes, so that kind of parental love would play a part in this conflict.
I do wonder who the villain will be, and how dangerous he or she is compared to Syndrome. But I really shouldn't start making comparisons, because either way, it looks like the movie will focus on family as much as it did in the first film, and it's going to be nice to see. So yeah, I'm happy and excited about the news, and I wish Pixar well on it. They took a risk in stepping out of their comfort zone, it paid off fantastically, and now the pressure is going to be on their shoulders to make a good sequel. Because in all honesty, I think it's going to be difficult to top The Incredibles, more-so than it was with Toy Story. But I have faith in them.